Programs & Examples On #Documentviewer

A WPF UI control that can host paginated FixedDocument content such as an XpsDocument.

How to initialize an array in angular2 and typescript

hi @JackSlayer94 please find the below example to understand how to make an array of size 5.

_x000D_
_x000D_
class Hero {_x000D_
    name: string;_x000D_
    constructor(text: string) {_x000D_
        this.name = text;_x000D_
    }_x000D_
_x000D_
    display() {_x000D_
        return "Hello, " + this.name;_x000D_
    }_x000D_
_x000D_
}_x000D_
_x000D_
let heros:Hero[] = new Array(5);_x000D_
for (let i = 0; i < 5; i++){_x000D_
    heros[i] = new Hero("Name: " + i);_x000D_
}_x000D_
_x000D_
for (let i = 0; i < 5; i++){_x000D_
    console.log(heros[i].display());_x000D_
}
_x000D_
_x000D_
_x000D_

How to get the week day name from a date?

SQL> SELECT TO_CHAR(date '1982-03-09', 'DAY') day FROM dual;

DAY
---------
TUESDAY

SQL> SELECT TO_CHAR(date '1982-03-09', 'DY') day FROM dual;

DAY
---
TUE

SQL> SELECT TO_CHAR(date '1982-03-09', 'Dy') day FROM dual;

DAY
---
Tue

(Note that the queries use ANSI date literals, which follow the ISO-8601 date standard and avoid date format ambiguity.)

How to use code to open a modal in Angular 2?

The Way i used to do it without lots of coding is.. I have the hidden button with the id="employeeRegistered"

On my .ts file I import ElementRef from '@angular/core'

Then after I process everything on my (click) method do as follow:

this.el.nativeElement.querySelector('#employeeRegistered').click();

then the modal displays as expected..

How to call a function in shell Scripting?

Summary:

  • Define functions before using them.
  • Once defined, treat them as commands.

Consider this script, called funcdemo:

#!/bin/bash

[ $# = 0 ] && exhort "write nastygram"

exhort(){
    echo "Please, please do not forget to $*"
}

[ $# != 0 ] && exhort "write begging letter"

In use:

$ funcdemo
./funcdemo: line 3: exhort: command not found
$ funcdemo 1
Please, please do not forget to write begging letter
$

Note the potential for a missing function to lie undiscovered for a long time (think 'by a customer at the most critical wrong moment'). It only matters whether the function exists when it is executed, the same as it only matters whether any other command exists when you try to execute it. Indeed, until it goes to execute the command, the shell neither knows nor cares whether it is an external command or a function.

HTML button opening link in new tab

You can use the following.

window.open(
  'https://google.com',
  '_blank' // <- This is what makes it open in a new window.
);

in HTML

 <button class="btn btn-success" onclick=" window.open('http://google.com','_blank')"> Google</button>

plunkr

Error - "UNION operator must have an equal number of expressions" when using CTE for recursive selection

Although this an old post, I am sharing another working example.

"COLUMN COUNT AS WELL AS EACH COLUMN DATATYPE MUST MATCH WHEN 'UNION' OR 'UNION ALL' IS USED"

Let us take an example:

1:

In SQL if we write - SELECT 'column1', 'column2' (NOTE: remember to specify names in quotes) In a result set, it will display empty columns with two headers - column1 and column2

2: I share one simple instance I came across.

I had seven columns with few different datatypes in SQL. I.e. uniqueidentifier, datetime, nvarchar

My task was to retrieve comma separated result set with column header. So that when I export the data to CSV I have comma separated rows with first row as header and has respective column names.

SELECT CONVERT(NVARCHAR(36), 'Event ID') + ', ' + 
'Last Name' + ', ' + 
'First Name' + ', ' + 
'Middle Name' + ', ' + 
CONVERT(NVARCHAR(36), 'Document Type') + ', ' + 
'Event Type' + ', ' + 
CONVERT(VARCHAR(23), 'Last Updated', 126)

UNION ALL

SELECT CONVERT(NVARCHAR(36), inspectionid) + ', ' + 
       individuallastname + ', ' + 
       individualfirstname + ', ' + 
       individualmiddlename + ', ' +
       CONVERT(NVARCHAR(36), documenttype) + ', ' + 
       'I' + ', ' +
       CONVERT(VARCHAR(23), modifiedon, 126)
FROM Inspection

Above, columns 'inspectionid' & 'documenttype' has uniqueidentifer datatype and so applied CONVERT(NVARCHAR(36)). column 'modifiedon' is datetime and so applied CONVERT(NVARCHAR(23), 'modifiedon', 126).

Parallel to above 2nd SELECT query matched 1st SELECT query as per datatype of each column.

Change Twitter Bootstrap Tooltip content on click

In Bootstrap 3 it is sufficient to call elt.attr('data-original-title', "Foo") as changes in the "data-original-title" attribute already trigger changes in the tooltip display.

UPDATE: You can add .tooltip('show') to show the changes immediately, you need not to mouseout and mouseover target to see the change in the title

elt.attr('data-original-title', "Foo").tooltip('show');

How do I read input character-by-character in Java?

Wrap your reader in a BufferedReader, which maintains a buffer allowing for much faster reads overall. You can then use read() to read a single character (which you'll need to cast). You can also use readLine() to fetch an entire line and then break that into individual characters. The BufferedReader also supports marking and returning, so if you need to, you can read a line multiple times.

Generally speaking, you want to use a BufferedReader or BufferedInputStream on top of whatever stream you are actually using since the buffer they maintain will make multiple reads much faster.

Using HTML5/JavaScript to generate and save a file

You can use localStorage. This is the Html5 equivalent of cookies. It appears to work on Chrome and Firefox BUT on Firefox, I needed to upload it to a server. That is, testing directly on my home computer didn't work.

I'm working up HTML5 examples. Go to http://faculty.purchase.edu/jeanine.meyer/html5/html5explain.html and scroll to the maze one. The information to re-build the maze is stored using localStorage.

I came to this article looking for HTML5 JavaScript for loading and working with xml files. Is it the same as older html and JavaScript????

How do you execute an arbitrary native command from a string?

The accepted answer wasn't working for me when trying to parse the registry for uninstall strings, and execute them. Turns out I didn't need the call to Invoke-Expression after all.

I finally came across this nice template for seeing how to execute uninstall strings:

$path = 'HKLM:\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall'
$app = 'MyApp'
$apps= @{}
Get-ChildItem $path | 
    Where-Object -FilterScript {$_.getvalue('DisplayName') -like $app} | 
    ForEach-Object -process {$apps.Set_Item(
        $_.getvalue('UninstallString'),
        $_.getvalue('DisplayName'))
    }

foreach ($uninstall_string in $apps.GetEnumerator()) {
    $uninstall_app, $uninstall_arg = $uninstall_string.name.split(' ')
    & $uninstall_app $uninstall_arg
}

This works for me, namely because $app is an in house application that I know will only have two arguments. For more complex uninstall strings you may want to use the join operator. Also, I just used a hash-map, but really, you'd probably want to use an array.

Also, if you do have multiple versions of the same application installed, this uninstaller will cycle through them all at once, which confuses MsiExec.exe, so there's that too.

Avoiding "resource is out of sync with the filesystem"

This happens to me all the time.

Go to the error log, find the exception, and open a few levels until you can see something more like a root cause. Does it says "Resource is out of sync with the file system" ?

When renaming packages, of course, Eclipse has to move files around in the file system. Apparently what happens is that it later discovers that something it thinks it needs to clean up has been renamed, can't find it, throws an exception.

There are a couple of things you might try. First, go to Window: Preferences, Workspace, and enable "Refresh Automatically". In theory this should fix the problem, but for me, it didn't.

Second, if you are doing a large refactoring with subpackages, do the subpackages one at a time, from the bottom up, and explicitly refresh with the file system after each subpackage is renamed.

Third, just ignore the error: when the error dialog comes up, click Abort to preserve the partial change, instead of rolling it back. Try it again, and again, and you may find you can get through the entire operation using multiple retries.

Setting HTTP headers

Do not use '*' for Origin, until You really need a completely public behavior.
As Wikipedia says:

"The value of "*" is special in that it does not allow requests to supply credentials, meaning HTTP authentication, client-side SSL certificates, nor does it allow cookies to be sent."

That means, you'll get a lot of errors, especially in Chrome when you'll try to implement for example a simple authentication.

Here is a corrected wrapper:

// Code has not been tested.
func addDefaultHeaders(fn http.HandlerFunc) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        if origin := r.Header.Get("Origin"); origin != "" {
            w.Header().Set("Access-Control-Allow-Origin", origin)
        }
        w.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE")
        w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token")
        w.Header().Set("Access-Control-Allow-Credentials", "true")
        fn(w, r)
    }
}

And don't forget to reply all these headers to the preflight OPTIONS request.

How do I generate random numbers in Dart?

try this, you can control the min/max value :

import 'dart:math';

void main(){
  random(min, max){
    var rn = new Random();
    return min + rn.nextInt(max - min);
  }
  print(random(5,20)); // Output : 19, 6, 15..
}

How to set String's font size, style in Java using the Font class?

Look here http://docs.oracle.com/javase/6/docs/api/java/awt/Font.html#deriveFont%28float%29

JComponent has a setFont() method. You will control the font there, not on the String.

Such as

JButton b = new JButton();
b.setFont(b.getFont().deriveFont(18.0f));

How to place Text and an Image next to each other in HTML?

img {
    float:left;
}
h3 {
    float:right;
}

jsFiddle example

Note that you will probably want to use the style clear:both on whatever elements comes after the code you provided so that it doesn't slide up directly beneath the floated elements.

How to change button text in Swift Xcode 6?

NOTE:

line

someButton.setTitle("New Title", forState: .normal)

works only when Title type is Plain.

enter image description here

How can I get LINQ to return the object which has the max value for a given property?

You could use a captured variable.

Item result = items.FirstOrDefault();
items.ForEach(x =>
{
  if(result.ID < x.ID)
    result = x;
});

Checking if an input field is required using jQuery

The below code works fine but I am not sure about the radio button and dropdown list

$( '#form_id' ).submit( function( event ) {
    event.preventDefault();

    //validate fields
    var fail = false;
    var fail_log = '';
    var name;
    $( '#form_id' ).find( 'select, textarea, input' ).each(function(){
        if( ! $( this ).prop( 'required' )){

        } else {
            if ( ! $( this ).val() ) {
                fail = true;
                name = $( this ).attr( 'name' );
                fail_log += name + " is required \n";
            }

        }
    });

    //submit if fail never got set to true
    if ( ! fail ) {
        //process form here.
    } else {
        alert( fail_log );
    }

});

How to overwrite styling in Twitter Bootstrap

You can overwrite a CSS class by making it "more specific".

You go up the HTML tree, and specify parent elements:

div.sidebar { ... } is more specific than .sidebar { ... }

You can go all the way up to BODY if you need to:

body .sidebar { ... } will override virtually anything.

See this handy guide: http://css-tricks.com/855-specifics-on-css-specificity/

Last executed queries for a specific database

This works for me to find queries on any database in the instance. I'm sysadmin on the instance (check your privileges):

SELECT deqs.last_execution_time AS [Time], dest.text AS [Query], dest.*
FROM sys.dm_exec_query_stats AS deqs
CROSS APPLY sys.dm_exec_sql_text(deqs.sql_handle) AS dest
WHERE dest.dbid = DB_ID('msdb')
ORDER BY deqs.last_execution_time DESC

This is the same answer that Aaron Bertrand provided but it wasn't placed in an answer.

UIAlertView first deprecated IOS 9

//Calling     
[self showMessage:@"There is no internet connection for this device"
                    withTitle:@"Error"];

//Method

-(void)showMessage:(NSString*)message withTitle:(NSString *)title
{

 UIAlertController * alert=   [UIAlertController
                                  alertControllerWithTitle:title
                                  message:message
                                  preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){

        //do something when click button
    }];
    [alert addAction:okAction];
    UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
    [vc presentViewController:alert animated:YES completion:nil];
}

If you want to use this alert in NSObject class you should use like:

-(void)showMessage:(NSString*)message withTitle:(NSString *)title{
dispatch_async(dispatch_get_main_queue(), ^{
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
    [alertController addAction:[UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {

    }]];

    [[[[UIApplication sharedApplication] keyWindow] rootViewController] presentViewController:alertController animated:YES completion:^{
    }];
});
}

How to draw a graph in PHP?

pChart is another great PHP graphing library.

What does functools.wraps do?

I very often use classes, rather than functions, for my decorators. I was having some trouble with this because an object won't have all the same attributes that are expected of a function. For example, an object won't have the attribute __name__. I had a specific issue with this that was pretty hard to trace where Django was reporting the error "object has no attribute '__name__'". Unfortunately, for class-style decorators, I don't believe that @wrap will do the job. I have instead created a base decorator class like so:

class DecBase(object):
    func = None

    def __init__(self, func):
        self.__func = func

    def __getattribute__(self, name):
        if name == "func":
            return super(DecBase, self).__getattribute__(name)

        return self.func.__getattribute__(name)

    def __setattr__(self, name, value):
        if name == "func":
            return super(DecBase, self).__setattr__(name, value)

        return self.func.__setattr__(name, value)

This class proxies all the attribute calls over to the function that is being decorated. So, you can now create a simple decorator that checks that 2 arguments are specified like so:

class process_login(DecBase):
    def __call__(self, *args):
        if len(args) != 2:
            raise Exception("You can only specify two arguments")

        return self.func(*args)

How to restart service using command prompt?

To restart a running service:

net stop "service name" && net start "service name"

However, if you don't know if the service is running in the first place and want to restart or start it, use this:

net stop "service name" & net start "service name"

This works if the service is already running or not.

For reference, here is the documentation on conditional processing symbols.

PostgreSQL JOIN data from 3 tables

Something like:

select t1.name, t2.image_id, t3.path
from table1 t1 inner join table2 t2 on t1.person_id = t2.person_id
inner join table3 t3 on t2.image_id=t3.image_id

If else embedding inside html

You will find multiple different methods that people use and they each have there own place.

<?php if($first_condition): ?>
  /*$first_condition is true*/
<?php elseif ($second_condition): ?>
  /*$first_condition is false and $second_condition is true*/
<?php else: ?>
  /*$first_condition and $second_condition are false*/
<?php endif; ?>

If in your php.ini attribute short_open_tag = true (this is normally found on line 141 of the default php.ini file) you can replace your php open tag from <?php to <?. This is not advised as most live server environments have this turned off (including many CMS's like Drupal, WordPress and Joomla). I have already tested short hand open tags in Drupal and confirmed that it will break your site, so stick with <?php. short_open_tag is not on by default in all server configurations and must not be assumed as such when developing for unknown server configurations. Many hosting companies have short_open_tag turned off.

A quick search of short_open_tag in stackExchange shows 830 results. https://stackoverflow.com/search?q=short_open_tag That's a lot of people having problems with something they should just not play with.

with some server environments and applications, short hand php open tags will still crash your code even with short_open_tag set to true.

short_open_tag will be removed in PHP6 so don't use short hand tags.

all future PHP versions will be dropping short_open_tag

"It's been recommended for several years that you not use the short tag "short cut" and instead to use the full tag combination. With the wide spread use of XML and use of these tags by other languages, the server can become easily confused and end up parsing the wrong code in the wrong context. But because this short cut has been a feature for such a long time, it's currently still supported for backwards compatibility, but we recommend you don't use them." – Jelmer Sep 25 '12 at 9:00 php: "short_open_tag = On" not working

and

Normally you write PHP like so: . However if allow_short_tags directive is enabled you're able to use: . Also sort tags provides extra syntax: which is equal to .

Short tags might seem cool but they're not. They causes only more problems. Oh... and IIRC they'll be removed from PHP6. Crozin answered Aug 24 '10 at 22:12 php short_open_tag problem

and

To answer the why part, I'd quote Zend PHP 5 certification guide: "Short tags were, for a time, the standard in the PHP world; however, they do have the major drawback of conflicting with XML headers and, therefore, have somewhat fallen by the wayside." – Fluffy Apr 13 '11 at 14:40 Are PHP short tags acceptable to use?

You may also see people use the following example:

<?php if($first_condition){ ?>
  /*$first_condition is true*/
<?php }else if ($second_condition){ ?>
  /*$first_condition is false and $second_condition is true*/
<?php }else{ ?>
  /*$first_condition and $second_condition are false*/
<?php } ?>

This will work but it is highly frowned upon as it's not considered as legible and is not what you would use this format for. If you had a PHP file where you had a block of PHP code that didn't have embedded tags inside, then you would use the bracket format.

The following example shows when to use the bracket method

<?php
if($first_condition){
   /*$first_condition is true*/
}else if ($second_condition){
   /*$first_condition is false and $second_condition is true*/
}else{
   /*$first_condition and $second_condition are false*/
}
?>

If you're doing this code for yourself you can do what you like, but if your working with a team at a job it is advised to use the correct format for the correct circumstance. If you use brackets in embedded html/php scripts that is a good way to get fired, as no one will want to clean up your code after you. IT bosses will care about code legibility and college professors grade on legibility.

UPDATE

based on comments from duskwuff its still unclear if shorthand is discouraged (by the php standards) or not. I'll update this answer as I get more information. But based on many documents found on the web about shorthand being bad for portability. I would still personally not use it as it gives no advantage and you must rely on a setting being on that is not on for every web host.

How to set default values in Go structs

There is a way of doing this with tags, which allows for multiple defaults.

Assume you have the following struct, with 2 default tags default0 and default1.

type A struct {
   I int    `default0:"3" default1:"42"`
   S string `default0:"Some String..." default1:"Some Other String..."`
}

Now it's possible to Set the defaults.

func main() {

ptr := &A{}

Set(ptr, "default0")
fmt.Printf("ptr.I=%d ptr.S=%s\n", ptr.I, ptr.S)
// ptr.I=3 ptr.S=Some String...

Set(ptr, "default1")
fmt.Printf("ptr.I=%d ptr.S=%s\n", ptr.I, ptr.S)
// ptr.I=42 ptr.S=Some Other String...
}

Here's the complete program in a playground.

If you're interested in a more complex example, say with slices and maps, then, take a look at creasty/defaultse

How can bcrypt have built-in salts?

This is from PasswordEncoder interface documentation from Spring Security,

 * @param rawPassword the raw password to encode and match
 * @param encodedPassword the encoded password from storage to compare with
 * @return true if the raw password, after encoding, matches the encoded password from
 * storage
 */
boolean matches(CharSequence rawPassword, String encodedPassword);

Which means, one will need to match rawPassword that user will enter again upon next login and matches it with Bcrypt encoded password that's stores in database during previous login/registration.

Eclipse memory settings when getting "Java Heap Space" and "Out of Memory"

-xms is the start memory (at the VM start), -xmx is the maximum memory for the VM

  • eclipse.ini : the memory for the VM running eclipse
  • jre setting : the memory for java programs run from eclipse
  • catalina.sh : the memory for your tomcat server

Python list iterator behavior and next(iterator)

What you see is the interpreter echoing back the return value of next() in addition to i being printed each iteration:

>>> a = iter(list(range(10)))
>>> for i in a:
...    print(i)
...    next(a)
... 
0
1
2
3
4
5
6
7
8
9

So 0 is the output of print(i), 1 the return value from next(), echoed by the interactive interpreter, etc. There are just 5 iterations, each iteration resulting in 2 lines being written to the terminal.

If you assign the output of next() things work as expected:

>>> a = iter(list(range(10)))
>>> for i in a:
...    print(i)
...    _ = next(a)
... 
0
2
4
6
8

or print extra information to differentiate the print() output from the interactive interpreter echo:

>>> a = iter(list(range(10)))
>>> for i in a:
...    print('Printing: {}'.format(i))
...    next(a)
... 
Printing: 0
1
Printing: 2
3
Printing: 4
5
Printing: 6
7
Printing: 8
9

In other words, next() is working as expected, but because it returns the next value from the iterator, echoed by the interactive interpreter, you are led to believe that the loop has its own iterator copy somehow.

How to get current date time in milliseconds in android

The problem is that System. currentTimeMillis(); returns the number of milliseconds from 1970-01-01T00:00:00Z, but new Date() gives the current local time. Adding the ZONE_OFFSET and DST_OFFSET from the Calendar class gives you the time in UTC.

Calendar rightNow = Calendar.getInstance();

// offset to add since we're not UTC

long offset = rightNow.get(Calendar.ZONE_OFFSET) +
    rightNow.get(Calendar.DST_OFFSET);

long sinceMidnight = (rightNow.getTimeInMillis() + offset) %
    (24 * 60 * 60 * 1000);

System.out.println(sinceMidnight + " milliseconds since midnight");

What are the differences between git branch, fork, fetch, merge, rebase and clone?

A clone is simply a copy of a repository. On the surface, its result is equivalent to svn checkout, where you download source code from some other repository. The difference between centralized VCS like Subversion and DVCSs like Git is that in Git, when you clone, you are actually copying the entire source repository, including all the history and branches. You now have a new repository on your machine and any commits you make go into that repository. Nobody will see any changes until you push those commits to another repository (or the original one) or until someone pulls commits from your repository, if it is publicly accessible.

A branch is something that is within a repository. Conceptually, it represents a thread of development. You usually have a master branch, but you may also have a branch where you are working on some feature xyz, and another one to fix bug abc. When you have checked out a branch, any commits you make will stay on that branch and not be shared with other branches until you merge them with or rebase them onto the branch in question. Of course, Git seems a little weird when it comes to branches until you look at the underlying model of how branches are implemented. Rather than explain it myself (I've already said too much, methinks), I'll link to the "computer science" explanation of how Git models branches and commits, taken from the Git website:

http://eagain.net/articles/git-for-computer-scientists/

A fork isn't a Git concept really, it's more a political/social idea. That is, if some people aren't happy with the way a project is going, they can take the source code and work on it themselves separate from the original developers. That would be considered a fork. Git makes forking easy because everyone already has their own "master" copy of the source code, so it's as simple as cutting ties with the original project developers and doesn't require exporting history from a shared repository like you might have to do with SVN.

EDIT: since I was not aware of the modern definition of "fork" as used by sites such as GitHub, please take a look at the comments and also Michael Durrant's answer below mine for more information.

Installing Tomcat 7 as Service on Windows Server 2008

  1. Edit service.bat – Swap two lines so that they appear in following order: if not “%JAVA_HOME%“ == ““ goto got JdkHome if not “%JRE_HOME%“ == ““ goto got JreHome
  2. Open cmd and run command service.bat install
  3. Open Services and find Apache Tomcat 7.0 Tomcat7. Right click and Properties. Change its startup type to Automatic (with delay).
  4. Reboot machine to verify if the service started automatically

Disable webkit's spin buttons on input type="number"?

The below css works for both Chrome and Firefox

input[type=number]::-webkit-outer-spin-button,
input[type=number]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

input[type=number] {
    -moz-appearance:textfield;
}

How to make a query with group_concat in sql server

Query:

SELECT
      m.maskid
    , m.maskname
    , m.schoolid
    , s.schoolname
    , maskdetail = STUFF((
          SELECT ',' + md.maskdetail
          FROM dbo.maskdetails md
          WHERE m.maskid = md.maskid
          FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, '')
FROM dbo.tblmask m
JOIN dbo.school s ON s.ID = m.schoolid
ORDER BY m.maskname

Additional information:

String Aggregation in the World of SQL Server

Check if a String is in an ArrayList of Strings

temp = bankAccNos.contains(no) ? 1 : 2;

Remove border from IFrame

Either add the frameBorder attribute, or use style with border-width 0px;, or set border style equal to none.

use any one from below 3:

_x000D_
_x000D_
<iframe src="myURL" width="300" height="300" style="border-width:0px;">Browser not compatible.</iframe>_x000D_
_x000D_
<iframe src="myURL" width="300" height="300" frameborder="0">Browser not compatible.</iframe>_x000D_
_x000D_
<iframe src="myURL" width="300" height="300" style="border:none;">Browser not compatible.</iframe>
_x000D_
_x000D_
_x000D_

Call to a member function fetch_assoc() on boolean in <path>

OK, i just fixed this error.

This happens when there is an error in query or table doesn't exist.

Try debugging the query buy running it directly on phpmyadmin to confirm the validity of the mysql Query

Batch file. Delete all files and folders in a directory

You cannot delete everything with either rmdir or del alone:

  • rmdir /s /q does not accept wildcard params. So rmdir /s /q * will error.
  • del /s /f /q will delete all files, but empty subdirectories will remain.

My preferred solution (as I have used in many other batch files) is:

rmdir /s /q . 2>NUL

CSS table layout: why does table-row not accept a margin?

The closest thing I've seen would be to set border-spacing: 0 30px; to the container div. However, this just leaves me with space on the upper edge of the table, which defeats the purpose, since you wanted margin-bottom.

Bridged networking not working in Virtualbox under Windows 10

I faced the same problem today after updating the Virtual Box. Got resolved by uninstalling Virtual Box and moving back to old version V5.2.8

powershell 2.0 try catch how to access the exception

Try something like this:

try {
    $w = New-Object net.WebClient
    $d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
    Write-Host $_.Exception.ToString()
}

The exception is in the $_ variable. You might explore $_ like this:

try {
    $w = New-Object net.WebClient
    $d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
    $_ | fl * -Force
}

I think it will give you all the info you need.

My rule: if there is some data that is not displayed, try to use -force.

List rows after specific date

Simply put:

SELECT * 
FROM TABLE_NAME
WHERE
dob > '1/21/2012'

Where 1/21/2012 is the date and you want all data, including that date.

SELECT * 
FROM TABLE_NAME
WHERE
dob BETWEEN '1/21/2012' AND '2/22/2012'

Use a between if you're selecting time between two dates

Set custom HTML5 required field validation message

Try this:

$(function() {
    var elements = document.getElementsByName("topicName");
    for (var i = 0; i < elements.length; i++) {
        elements[i].oninvalid = function(e) {
            e.target.setCustomValidity("Please enter Room Topic Title");
        };
    }
})

I tested this in Chrome and FF and it worked in both browsers.

Display HTML form values in same page after submit using Ajax

This works.

<html>
<head>
<script type = "text/javascript">
function write_below(form)
{
var input = document.forms.write.input_to_write.value;
document.getElementById('write_here').innerHTML="Your input was:"+input;
return false;
}
</script>
</head>

<!--Insert more code here-->
<body>
<form name='write' onsubmit='return write_below(this);'>
<input type = "text" name='input_to_write'>
<input type = "button" value = "submit" />
</form>
<div id='write_here'></div></body>
</html>

Returning false from the function never posts it to other page,but does edit the html content.

Regex for 1 or 2 digits, optional non-alphanumeric, 2 known alphas

^[0-9]{1,2}[:.,-]?po$

Add any other allowable non-alphanumeric characters to the middle brackets to allow them to be parsed as well.

Initialize a long in Java

To initialize long you need to append "L" to the end.
It can be either uppercase or lowercase.

All the numeric values are by default int. Even when you do any operation of byte with any integer, byte is first promoted to int and then any operations are performed.

Try this

byte a = 1; // declare a byte
a = a*2; //  you will get error here

You get error because 2 is by default int.
Hence you are trying to multiply byte with int. Hence result gets typecasted to int which can't be assigned back to byte.

Import Python Script Into Another?

Hope this work

def break_words(stuff):
    """This function will break up words for us."""
    words = stuff.split(' ')
    return words

def sort_words(words):
    """Sorts the words."""
    return sorted(words)

def print_first_word(words):
    """Prints the first word after popping it off."""
    word = words.pop(0)
    print (word)

def print_last_word(words):
    """Prints the last word after popping it off."""
    word = words.pop(-1)
    print(word)

def sort_sentence(sentence):
    """Takes in a full sentence and returns the sorted words."""
    words = break_words(sentence)
    return sort_words(words)

def print_first_and_last(sentence):
    """Prints the first and last words of the sentence."""
    words = break_words(sentence)
    print_first_word(words)
    print_last_word(words)

def print_first_and_last_sorted(sentence):
    """Sorts the words then prints the first and last one."""
    words = sort_sentence(sentence)
    print_first_word(words)
    print_last_word(words)


print ("Let's practice everything.")
print ('You\'d need to know \'bout escapes with \\ that do \n newlines and \t tabs.')

poem = """
\tThe lovely world
with logic so firmly planted
cannot discern \n the needs of love
nor comprehend passion from intuition
and requires an explantion
\n\t\twhere there is none.
"""


print ("--------------")
print (poem)
print ("--------------")

five = 10 - 2 + 3 - 5
print ("This should be five: %s" % five)

def secret_formula(start_point):
    jelly_beans = start_point * 500
    jars = jelly_beans / 1000
    crates = jars / 100
    return jelly_beans, jars, crates


start_point = 10000
jelly_beans, jars, crates = secret_formula(start_point)

print ("With a starting point of: %d" % start_point)
print ("We'd have %d jeans, %d jars, and %d crates." % (jelly_beans, jars, crates))

start_point = start_point / 10

print ("We can also do that this way:")
print ("We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_point))


sentence = "All god\tthings come to those who weight."

words =  break_words(sentence)
sorted_words =  sort_words(words)

print_first_word(words)
print_last_word(words)
print_first_word(sorted_words)
print_last_word(sorted_words)
sorted_words =  sort_sentence(sentence)
print (sorted_words)

print_first_and_last(sentence)
print_first_and_last_sorted(sentence)

Check if all elements in a list are identical

A solution faster than using set() that works on sequences (not iterables) is to simply count the first element. This assumes the list is non-empty (but that's trivial to check, and decide yourself what the outcome should be on an empty list)

x.count(x[0]) == len(x)

some simple benchmarks:

>>> timeit.timeit('len(set(s1))<=1', 's1=[1]*5000', number=10000)
1.4383411407470703
>>> timeit.timeit('len(set(s1))<=1', 's1=[1]*4999+[2]', number=10000)
1.4765670299530029
>>> timeit.timeit('s1.count(s1[0])==len(s1)', 's1=[1]*5000', number=10000)
0.26274609565734863
>>> timeit.timeit('s1.count(s1[0])==len(s1)', 's1=[1]*4999+[2]', number=10000)
0.25654196739196777

How to get the max of two values in MySQL?

You can use GREATEST function with not nullable fields. If one of this values (or both) can be NULL, don't use it (result can be NULL).

select 
    if(
        fieldA is NULL, 
        if(fieldB is NULL, NULL, fieldB), /* second NULL is default value */
        if(fieldB is NULL, field A, GREATEST(fieldA, fieldB))
    ) as maxValue

You can change NULL to your preferred default value (if both values is NULL).

What exactly is \r in C language?

That is not always true; it only works in Windows.
For interacting with terminal in putty, Linux shell,... it will be used for returning the cursor to the beginning of line. following picture shows the usage of that:

Without '\r':

Data comes without '\r' to the putty terminal, it has just '\n'.
it means that data will be printed just in next line.

enter image description here

With '\r':

Data comes with '\r', i.e. string ends with '\r\n'. So the cursor in putty terminal not only will go to the next line but also at the beginning of line

enter image description here

How to convert NSData to byte array in iPhone?

Here's what I believe is the Swift equivalent:

if let data = NSData(contentsOfFile: filePath) {
   let length = data.length
   let byteData = malloc(length)
   memcmp(byteData, data.bytes, length)
}

FIX CSS <!--[if lt IE 8]> in IE

<!--[if lt IE 8]><![endif]-->

The lt in the above statement means less than, so 'if less than IE 8'.

For all versions of IE you can just use

<!--[if IE]><![endif]-->

or for all versions above ie 6 for example.

<!--[if gt IE 6]><![endif]-->

Where gt is 'greater than'

If you would like to write specific styles for versions below and including IE8 you can write

<!--[if lte IE 8]><![endif]-->

where lte is 'less than and equal' to

PHP array delete by value (not key)

I think the simplest way would be to use a function with a foreach loop:

//This functions deletes the elements of an array $original that are equivalent to the value $del_val
//The function works by reference, which means that the actual array used as parameter will be modified.

function delete_value(&$original, $del_val)
{
    //make a copy of the original, to avoid problems of modifying an array that is being currently iterated through
    $copy = $original;
    foreach ($original as $key => $value)
    {
        //for each value evaluate if it is equivalent to the one to be deleted, and if it is capture its key name.
        if($del_val === $value) $del_key[] = $key;
    };
    //If there was a value found, delete all its instances
    if($del_key !== null)
    {
        foreach ($del_key as $dk_i)
        {
            unset($original[$dk_i]);
        };
        //optional reordering of the keys. WARNING: only use it with arrays with numeric indexes!
        /*
        $copy = $original;
        $original = array();
        foreach ($copy as $value) {
            $original[] = $value;
        };
        */
        //the value was found and deleted
        return true;
    };
    //The value was not found, nothing was deleted
    return false;
};

$original = array(0,1,2,3,4,5,6,7,4);
$del_val = 4;
var_dump($original);
delete_value($original, $del_val);
var_dump($original);

Output will be:

array(9) {
  [0]=>
  int(0)
  [1]=>
  int(1)
  [2]=>
  int(2)
  [3]=>
  int(3)
  [4]=>
  int(4)
  [5]=>
  int(5)
  [6]=>
  int(6)
  [7]=>
  int(7)
  [8]=>
  int(4)
}
array(7) {
  [0]=>
  int(0)
  [1]=>
  int(1)
  [2]=>
  int(2)
  [3]=>
  int(3)
  [5]=>
  int(5)
  [6]=>
  int(6)
  [7]=>
  int(7)
}

Parenthesis/Brackets Matching using Stack algorithm

public static bool IsBalanced(string input)
    {
        Dictionary<char, char> bracketPairs = new Dictionary<char, char>() {
        { '(', ')' },
        { '{', '}' },
        { '[', ']' },
        { '<', '>' }
    };

        Stack<char> brackets = new Stack<char>();

        try
        {
            // Iterate through each character in the input string
            foreach (char c in input)
            {
                // check if the character is one of the 'opening' brackets
                if (bracketPairs.Keys.Contains(c))
                {
                    // if yes, push to stack
                    brackets.Push(c);
                }
                else
                    // check if the character is one of the 'closing' brackets
                    if (bracketPairs.Values.Contains(c))
                    {
                        // check if the closing bracket matches the 'latest' 'opening' bracket
                        if (c == bracketPairs[brackets.First()])
                        {
                            brackets.Pop();
                        }
                        else
                            // if not, its an unbalanced string
                            return false;
                    }
                    else
                        // continue looking
                        continue;
            }
        }
        catch
        {
            // an exception will be caught in case a closing bracket is found, 
            // before any opening bracket.
            // that implies, the string is not balanced. Return false
            return false;
        }

        // Ensure all brackets are closed
        return brackets.Count() == 0 ? true : false;
    }

Flatten List in LINQ

With query syntax:

var values =
from inner in outer
from value in inner
select value;

Laravel 5 - How to access image uploaded in storage within View?

If you are on windows you can run this command on cmd:

mklink /j /path/to/laravel/public/avatars /path/to/laravel/storage/avatars 

from: http://www.sevenforums.com/tutorials/278262-mklink-create-use-links-windows.html

JSON Array iteration in Android/Java

If you're using the JSON.org Java implementation, which is open source, you can just make JSONArray implement the Iterable interface and add the following method to the class:

@Override
public Iterator iterator() {
    return this.myArrayList.iterator();
}

This will make all instances of JSONArray iterable, meaning that the for (Object foo : bar) syntax will now work with it (note that foo has to be an Object, because JSONArrays do not have a declared type). All this works because the JSONArray class is backed by a simple ArrayList, which is already iterable. I imagine that other open source implementations would be just as easy to change.

How to write LDAP query to test if user is member of a group?

I would add one more thing to Marc's answer: The memberOf attribute can't contain wildcards, so you can't say something like "memberof=CN=SPS*", and expect it to find all groups that start with "SPS".

adb not finding my device / phone (MacOS X)

For me this is what worked, I have a Huawei device and I had to install HiSuite from the AppStore, followed its instructions to enable HDB, then in my phone change USB mode to PTP and I started to see some popups about authorizing the device, after that adb devices detected the device.

How can I set the maximum length of 6 and minimum length of 6 in a textbox?

You can't set a minimum length on a text field. Otherwise, users wouldn't be able to type in the first five characters.

Your best bet is to validate the input when the form is submitted to ensure that the length is six.

maxlength is not a validation attribute. It is designed to prevent the user from physically typing in more than six characters. The corresponding minlengh is not in scope of the HTML specification, because its implementation would render the textbox unusable.

Regular Expression - 2 letters and 2 numbers in C#

You're missing an ending anchor.

if(Regex.IsMatch(myString, "^[A-Za-z]{2}[0-9]{2}\z")) {
    // ...
}

Here's a demo.


EDIT: If you can have anything between an initial 2 letters and a final 2 numbers:

if(Regex.IsMatch(myString, @"^[A-Za-z]{2}.*\d{2}\z")) {
    // ...
}

Here's a demo.

ASP.net using a form to insert data into an sql server table

Simple, make a simple asp page with the designer (just for the beginning) Lets say the body is something like this:

<body>
    <form id="form1" runat="server">
    <div>
        <asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
        <br />
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
    </div>
    <p>
        <asp:Button ID="Button1" runat="server" Text="Button" />
    </p>
    </form>
</body>

Great, now every asp object IS an object. So you can access it in the asp's CS code. The asp's CS code is triggered by events (mostly). The class will probably inherit from System.Web.UI.Page

If you go to the cs file of the asp page, you'll see a protected void Page_Load(object sender, EventArgs e) ... That's the load event, you can use that to populate data into your objects when the page loads.

Now, go to the button in your designer (Button1) and look at its properties, you can design it, or add events from there. Just change to the events view, and create a method for the event.

The button is a web control Button Add a Click event to the button call it Button1Click:

void Button1Click(Object sender,EventArgs e) { }

Now when you click the button, this method will be called. Because ASP is object oriented, you can think of the page as the actual class, and the objects will hold the actual current data.

So if for example you want to access the text in TextBox1 you just need to call that object in the C# code:

String firstBox = TextBox1.Text;

In the same way you can populate the objects when event occur.

Now that you have the data the user posted in the textboxes , you can use regular C# SQL connections to add the data to your database.

How do I right align div elements?

If you have multiple divs that you want aligned side by side at the right end of the parent div, set text-align: right; on the parent div.

Android global variable

There are a few different ways you can achieve what you are asking for.

1.) Extend the application class and instantiate your controller and model objects there.

public class FavoriteColorsApplication extends Application {

    private static FavoriteColorsApplication application;
    private FavoriteColorsService service;

    public FavoriteColorsApplication getInstance() {
        return application;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        application = this;
        application.initialize();
    }

    private void initialize() {
        service = new FavoriteColorsService();
    }

    public FavoriteColorsService getService() {
        return service;
    }

}

Then you can call the your singleton from your custom Application object at any time:

public class FavoriteColorsActivity extends Activity {

private FavoriteColorsService service = null;
private ArrayAdapter<String> adapter;
private List<String> favoriteColors = new ArrayList<String>();

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_favorite_colors);

    service = ((FavoriteColorsApplication) getApplication()).getService();
    favoriteColors = service.findAllColors();

    ListView lv = (ListView) findViewById(R.id.favoriteColorsListView);
    adapter = new ArrayAdapter<String>(this, R.layout.favorite_colors_list_item,
            favoriteColors);
    lv.setAdapter(adapter);
}

2.) You can have your controller just create a singleton instance of itself:

public class Controller {
    private static final String TAG = "Controller";
    private static sController sController;
    private Dao mDao;

    private Controller() {
        mDao = new Dao();    
    }

    public static Controller create() {
        if (sController == null) {
            sController = new Controller();
        }
        return sController;
    }
}

Then you can just call the create method from any Activity or Fragment and it will create a new controller if one doesn't already exist, otherwise it will return the preexisting controller.

3.) Finally, there is a slick framework created at Square which provides you dependency injection within Android. It is called Dagger. I won't go into how to use it here, but it is very slick if you need that sort of thing.

I hope I gave enough detail in regards to how you can do what you are hoping for.

Java, How to get number of messages in a topic in apache kafka

You may use kafkatool. Please check this link -> http://www.kafkatool.com/download.html

Kafka Tool is a GUI application for managing and using Apache Kafka clusters. It provides an intuitive UI that allows one to quickly view objects within a Kafka cluster as well as the messages stored in the topics of the cluster. enter image description here

Handlebars/Mustache - Is there a built in way to loop through the properties of an object?

I was using old version 1.0.beta.6 of handlebars, i think somewhere during 1.1 - 1.3 this functionality was added, so updating to 1.3.0 solved the issue, here is the usage:

Usage:

{{#each object}}
  Key {{@key}} : Value {{this}}
{{/people}}

How to define custom sort function in javascript?

function msort(arr){
    for(var i =0;i<arr.length;i++){
        for(var j= i+1;j<arr.length;j++){
            if(arr[i]>arr[j]){
                var swap = arr[i];
                arr[i] = arr[j];
                arr[j] = swap;
            }
        }
    }
return arr;
}

How to disable XDebug

In Linux Ubuntu(maybe also another - it's not tested) distribution with PHP 5 on board, you can use:

sudo php5dismod xdebug

And with PHP 7

sudo phpdismod xdebug

And after that, please restart the server:

sudo service apache2 restart

Stack array using pop() and push()

Here is an example of implementing stack in java (Array Based implementation):

public class MyStack extends Throwable{

/**
 * 
 */
private static final long serialVersionUID = -4433344892390700337L;

protected static int top = -1;
protected static int capacity;
protected static int size;

public int stackDatas[] = null;

public MyStack(){
    stackDatas = new int[10];
    capacity = stackDatas.length;
}

public static int size(){

    if(top < 0){
        size = top + 1;
        return size;
    }
    size = top+1;
    return size; 
}

public void push(int data){
    if(capacity == size()){
        System.out.println("no memory");
    }else{
        stackDatas[++top] = data;
    }
}

public boolean topData(){
    if(top < 0){
        return true;
    }else{
        System.out.println(stackDatas[top]);
        return false;
    }
}

public void pop(){
    if(top < 0){
        System.out.println("stack is empty");
    }else{
        int temp = stackDatas[top];
        stackDatas = ArrayUtils.remove(stackDatas, top--);
        System.out.println("poped data---> "+temp);
    }
}

public String toString(){
    String result = "[";

    if(top<0){
        return "[]";
    }else{


    for(int i = 0; i< size(); i++){
        result = result + stackDatas[i] +",";
    }
    }

    return result.substring(0, result.lastIndexOf(",")) +"]";
 }
}

calling MyStack:

    public class CallingMyStack {

public static MyStack ms;

public static void main(String[] args) {

    ms = new MyStack();
    ms.push(1);
    ms.push(2);
    ms.push(3);
    ms.push(4);
    ms.push(5);
    ms.push(6);
    ms.push(7);
    ms.push(8);
    ms.push(9);
    ms.push(10);
    System.out.println("size: "+MyStack.size());
    System.out.println("List---> "+ms);
    System.out.println("----------");
    ms.pop();
    ms.pop();
    ms.pop();
    ms.pop();
    System.out.println("List---> "+ms);
    System.out.println("size: "+MyStack.size());

 }
}

output:

size: 10
List---> [1,2,3,4,5,6,7,8,9,10]
----------
poped data---> 10
poped data---> 9
poped data---> 8
poped data---> 7
List---> [1,2,3,4,5,6]
size: 6

Replace X-axis with own values

Not sure if it's what you mean, but you can do this:

plot(1:10, xaxt = "n", xlab='Some Letters')
axis(1, at=1:10, labels=letters[1:10])

which then gives you the graph:

enter image description here

What does a (+) sign mean in an Oracle SQL WHERE clause?

This is an Oracle-specific notation for an outer join. It means that it will include all rows from t1, and use NULLS in the t0 columns if there is no corresponding row in t0.

In standard SQL one would write:

SELECT t0.foo, t1.bar
  FROM FIRST_TABLE t0
 RIGHT OUTER JOIN SECOND_TABLE t1;

Oracle recommends not to use those joins anymore if your version supports ANSI joins (LEFT/RIGHT JOIN) :

Oracle recommends that you use the FROM clause OUTER JOIN syntax rather than the Oracle join operator. Outer join queries that use the Oracle join operator (+) are subject to the following rules and restrictions […]

How do I make a fully statically linked .exe with Visual Studio Express 2005?

My experience in Visual Studio 2010 is that there are two changes needed so as to not need DLL's. From the project property page (right click on the project name in the Solution Explorer window):

  1. Under Configuration Properties --> General, change the "Use of MFC" field to "Use MFC in a Static Library".

  2. Under Configuration Properties --> C/C++ --> Code Generation, change the "Runtime Library" field to "Multi-Threaded (/MT)"

Not sure why both were needed. I used this to remove a dependency on glut32.dll.

Added later: When making these changes to the configurations, you should make them to "All Configurations" --- you can select this at the top of the Properties window. If you make the change to just the Debug configuration, it won't apply to the Release configuration, and vice-versa.

Sequence contains more than one element

As @Mehmet is pointing out, if your result is returning more then 1 elerment then you need to look into you data as i suspect that its not by design that you have customers sharing a customernumber.

But to the point i wanted to give you a quick overview.

//success on 0 or 1 in the list, returns dafault() of whats in the list if 0
list.SingleOrDefault();
//success on 1 and only 1 in the list
list.Single();

//success on 0-n, returns first element in the list or default() if 0 
list.FirstOrDefault();
//success 1-n, returns the first element in the list
list.First();

//success on 0-n, returns first element in the list or default() if 0 
list.LastOrDefault();
//success 1-n, returns the last element in the list
list.Last();

for more Linq expressions have a look at System.Linq.Expressions

How to get primary key column in Oracle?

Try This Code Here I created a table for get primary key column in oracle which is called test and then query

create table test
(
id int,
name varchar2(20),
city varchar2(20),
phone int,
constraint pk_id_name_city primary key (id,name,city)
);

SELECT cols.table_name, cols.column_name, cols.position, cons.status, cons.owner FROM all_constraints cons, all_cons_columns cols WHERE cols.table_name = 'TEST' AND cons.constraint_type = 'P' AND cons.constraint_name = cols.constraint_name AND cons.owner = cols.owner  ORDER BY cols.table_name, cols.position;

Fastest way to convert JavaScript NodeList to Array?

faster and shorter :

// nl is the nodelist
var a=[], l=nl.length>>>0;
for( ; l--; a[l]=nl[l] );

How to make layout with View fill the remaining space?

Using a ConstraintLayout, I've found something like

<Button
    android:id="@+id/left_button"
    android:layout_width="80dp"
    android:layout_height="48dp"
    android:text="&lt;"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

<TextView
    android:layout_width="0dp"
    android:layout_height="0dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toRightOf="@+id/left_button"
    app:layout_constraintRight_toLeftOf="@+id/right_button"
    app:layout_constraintTop_toTopOf="parent" />

<Button
    android:id="@+id/right_button"
    android:layout_width="80dp"
    android:layout_height="48dp"
    android:text="&gt;"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

works. The key is setting the right, left, top, and bottom edge constraints appropriately, then setting the width and height to 0dp and letting it figure out it's own size.

How do I encode and decode a base64 string?

Based on the answers by Andrew Fox and Cebe, I turned it around and made them string extensions instead of Base64String extensions.

public static class StringExtensions
{
    public static string ToBase64(this string text)
    {
        return ToBase64(text, Encoding.UTF8);
    }

    public static string ToBase64(this string text, Encoding encoding)
    {
        if (string.IsNullOrEmpty(text))
        {
            return text;
        }

        byte[] textAsBytes = encoding.GetBytes(text);
        return Convert.ToBase64String(textAsBytes);
    }

    public static bool TryParseBase64(this string text, out string decodedText)
    {
        return TryParseBase64(text, Encoding.UTF8, out decodedText);
    }

    public static bool TryParseBase64(this string text, Encoding encoding, out string decodedText)
    {
        if (string.IsNullOrEmpty(text))
        {
            decodedText = text;
            return false;
        }

        try
        {
            byte[] textAsBytes = Convert.FromBase64String(text);
            decodedText = encoding.GetString(textAsBytes);
            return true;
        }
        catch (Exception)
        {
            decodedText = null;
            return false;
        }
    }
}

Parse error: syntax error, unexpected T_ECHO in

Missing ; after var_dump($row)

Twitter Bootstrap vs jQuery UI?

We have used both and we like Bootstrap for its simplicity and the pace at which it's being developed and enhanced. The problem with jQuery UI is that it's moving at a snail's pace. It's taking years to roll out common features like Menubar, Tree control and DataGrid which are in planning/development stage for ever. We waited waited waited and finally given up and used other libraries like ExtJS for our product http://dblite.com.

Bootstrap has come up with quite a comprehensive set of features in a very short period of time and I am sure it will outpace jQuery UI pretty soon.

So I see no point in using something that will eventually be outdated...

How can apply multiple background color to one div

You can create something like c using CSS multiple-backgrounds.

div {
    background: linear-gradient(red, red),
                linear-gradient(blue, blue),
                linear-gradient(green, green);
    background-size: 30% 50%,
                     30% 60%,
                     40% 80%;
    background-position: 0% top,
                         calc(30% * 100 / (100 - 30)) top,
                         calc(60% * 100 / (100 - 40)) top;
    background-repeat: no-repeat;
}

Note, you still have to use linear-gradients for background types, because CSS will not allow you to control the background-size of a single color layer. So here we just make a single-color gradient. Then you can control the size/position of each of those blocks of color independently. You also have to make sure they don't repeat, or they'll just expand and cover the whole image.

The trickiest part here is background-position. A background-position of 0% puts your element's left edge at the left. 100% puts its right edge at the right. 50% centers is middle.

For a fun bit of math to solve that, you can guess the transform is probably linear, and just solve two little slope-intercept equations.

// (at 0%, the div's left edge is 0% from the left)
0 = m * 0 + b
// (at 100%, the div's right edge is 100% - width% from the left)
100 = m * (100 - width) + b
b = 0, m = 100 / (100 - width)

so to position our 40% wide div 60% from the left, we put it at 60% * 100 / (100 - 40) (or use css-calc).

Grid of responsive squares

You can make responsive grid of squares with verticaly and horizontaly centered content only with CSS. I will explain how in a step by step process but first here are 2 demos of what you can achieve :

Responsive 3x3 square grid Responsive square images in a 3x3 grid

Now let's see how to make these fancy responsive squares!



1. Making the responsive squares :

The trick for keeping elements square (or whatever other aspect ratio) is to use percent padding-bottom.
Side note: you can use top padding too or top/bottom margin but the background of the element won't display.

As top padding is calculated according to the width of the parent element (See MDN for reference), the height of the element will change according to its width. You can now Keep its aspect ratio according to its width.
At this point you can code :

HTML :

 <div></div>

CSS

div {
    width: 30%;
    padding-bottom: 30%; /* = width for a square aspect ratio */
}

Here is a simple layout example of 3*3 squares grid using the code above.

With this technique, you can make any other aspect ratio, here is a table giving the values of bottom padding according to the aspect ratio and a 30% width.

 Aspect ratio  |  padding-bottom  |  for 30% width
------------------------------------------------
    1:1        |  = width         |    30%
    1:2        |  width x 2       |    60%
    2:1        |  width x 0.5     |    15%
    4:3        |  width x 0.75    |    22.5%
    16:9       |  width x 0.5625  |    16.875%




2. Adding content inside the squares

As you can't add content directly inside the squares (it would expand their height and squares wouldn't be squares anymore) you need to create child elements (for this example I am using divs) inside them with position: absolute; and put the content inside them. This will take the content out of the flow and keep the size of the square.

Don't forget to add position:relative; on the parent divs so the absolute children are positioned/sized relatively to their parent.

Let's add some content to our 3x3 grid of squares :

HTML :

<div class="square">
    <div class="content">
        .. CONTENT HERE ..
    </div>
</div>
... and so on 9 times for 9 squares ...

CSS :

.square {
    float:left;
    position: relative;
    width: 30%;
    padding-bottom: 30%; /* = width for a 1:1 aspect ratio */
    margin:1.66%;
    overflow:hidden;
}

.content {
    position:absolute;
    height:80%; /* = 100% - 2*10% padding */
    width:90%; /* = 100% - 2*5% padding */
    padding: 10% 5%;
}

RESULT <-- with some formatting to make it pretty!



3.Centering the content

Horizontally :

This is pretty easy, you just need to add text-align:center to .content.
RESULT

Vertical alignment

This becomes serious! The trick is to use

display:table;
/* and */
display:table-cell;
vertical-align:middle;

but we can't use display:table; on .square or .content divs because it conflicts with position:absolute; so we need to create two children inside .content divs. Our code will be updated as follow :

HTML :

<div class="square">
    <div class="content">
        <div class="table">
            <div class="table-cell">
                ... CONTENT HERE ...
            </div>
        </div>
    </div>
</div>
... and so on 9 times for 9 squares ...

CSS :

.square {
    float:left;
    position: relative;
    width: 30%;
    padding-bottom : 30%; /* = width for a 1:1 aspect ratio */
    margin:1.66%;
    overflow:hidden;
}

.content {
    position:absolute;
    height:80%; /* = 100% - 2*10% padding */
    width:90%; /* = 100% - 2*5% padding */
    padding: 10% 5%;
}
.table{
    display:table;
    height:100%;
    width:100%;
}
.table-cell{
    display:table-cell;
    vertical-align:middle;
    height:100%;
    width:100%;
}




We have now finished and we can take a look at the result here :

LIVE FULLSCREEN RESULT

editable fiddle here


How to change a PG column to NULLABLE TRUE?

From the fine manual:

ALTER TABLE mytable ALTER COLUMN mycolumn DROP NOT NULL;

There's no need to specify the type when you're just changing the nullability.

Can't change table design in SQL Server 2008

Prevent saving changes that require table re-creation

Five swift clicks

Prevent saving changes that require table re-creation in five clicks

  1. Tools
  2. Options
  3. Designers
  4. Prevent saving changes that require table re-creation
  5. OK.

After saving, repeat the proceudure to re-tick the box. This safe-guards against accidental data loss.

Further explanation

  • By default SQL Server Management Studio prevents the dropping of tables, because when a table is dropped its data contents are lost.*

  • When altering a column's datatype in the table Design view, when saving the changes the database drops the table internally and then re-creates a new one.

*Your specific circumstances will not pose a consequence since your table is empty. I provide this explanation entirely to improve your understanding of the procedure.

Java replace all square brackets in a string

_x000D_
_x000D_
   Use this line:) String result = strCurBal.replaceAll("[(" what ever u need to remove ")]", "");_x000D_
_x000D_
    String strCurBal = "(+)3428";_x000D_
    Log.e("Agilanbu before omit ", strCurBal);_x000D_
    String result = strCurBal.replaceAll("[()]", ""); // () removing special characters from string_x000D_
    Log.e("Agilanbu after omit ", result);_x000D_
   _x000D_
    o/p :_x000D_
    Agilanbu before omit : (+)3428_x000D_
    Agilanbu after omit :  +3428_x000D_
_x000D_
    String finalVal = result.replaceAll("[+]", ""); // + removing special characters from string_x000D_
    Log.e("Agilanbu finalVal  ", finalVal);_x000D_
    o/p_x000D_
    Agilanbu finalVal : 3428_x000D_
            _x000D_
    String finalVal1 = result.replaceAll("[+]", "-"); // insert | append | replace the special characters from string_x000D_
    Log.e("Agilanbu finalVal  ", finalVal1);_x000D_
    o/p_x000D_
    Agilanbu finalVal : -3428  // replacing the + symbol to -
_x000D_
_x000D_
_x000D_

How do I set combobox read-only or user cannot write in a combo box only can select the given items?

Just change the DropDownStyle to DropDownList. Or if you want it completely read only you can set Enabled = false, or if you don't like the look of that I sometimes have two controls, one readonly textbox and one combobox and then hide the combo and show the textbox if it should be completely readonly and vice versa.

Making a list of evenly spaced numbers in a certain range in python

f = 0.5
a = 0
b = 9
d = [x * f for x in range(a, b)]

would be a way to do it.

Mapping a JDBC ResultSet to an object

If you don't want to use any JPA provider such as OpenJPA or Hibernate, you can just give Apache DbUtils a try.

http://commons.apache.org/proper/commons-dbutils/examples.html

Then your code will look like this:

QueryRunner run = new QueryRunner(dataSource);

// Use the BeanListHandler implementation to convert all
// ResultSet rows into a List of Person JavaBeans.
ResultSetHandler<List<Person>> h = new BeanListHandler<Person>(Person.class);

// Execute the SQL statement and return the results in a List of
// Person objects generated by the BeanListHandler.
List<Person> persons = run.query("SELECT * FROM Person", h);

Test if object implements interface

In addition to testing using the "is" operator, you can decorate your methods to make sure that variables passed to it implement a particular interface, like so:

public static void BubbleSort<T>(ref IList<T> unsorted_list) where T : IComparable
{
     //Some bubbly sorting
}

I'm not sure which version of .Net this was implemented in so it may not work in your version.

git: 'credential-cache' is not a git command

I fixed this issue by removing the credential section from the config of specific project:

  • Just typed: git config -e
  • Inside the editor I removed the whole section [credential] helper = cache.

This removed the annoying message :

git: 'credential-cache' is not a git command. See 'git --help'.

jQuery changing style of HTML element

you could also specify multiple style values like this

$('#navigation ul li').css({'display': 'inline-block','background-color': '#ff0000', 'color': '#ffffff'});

PHP 7 RC3: How to install missing MySQL PDO

I had, pretty much, the same problem. I was able to see that PDO was enabled but I had no available drivers (using PHP 7-RC4). I managed to resolve the issue by adding the php_pdo_mysql extension to those which were enabled.

Hope this helps!

Bootstrap 3 and Youtube in Modal

I put together this html/jQuery dynamic YouTube video modal script that auto plays the YouTube video when the trigger (link) is clicked, the trigger also contains the link to play. The script will find the native bootstrap modal call and open the shared modal template with the data from the trigger. See Below and let me know what you think. I would love to hear thoughts...

HTML MODAL TRIGGER:

 <a href="#" class="btn btn-default" data-toggle="modal" data-target="#videoModal" data-theVideo="http://www.youtube.com/embed/loFtozxZG0s" >VIDEO</a>

HTML MODAL VIDEO TEMPLATE:

<div class="modal fade" id="videoModal" tabindex="-1" role="dialog" aria-labelledby="videoModal" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-body">
        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
        <div>
          <iframe width="100%" height="350" src=""></iframe>
        </div>
      </div>
    </div>
  </div>
</div>

THE JQUERY FUNCTION:

//FUNCTION TO GET AND AUTO PLAY YOUTUBE VIDEO FROM DATATAG
function autoPlayYouTubeModal(){
  var trigger = $("body").find('[data-toggle="modal"]');
  trigger.click(function() {
    var theModal = $(this).data( "target" ),
    videoSRC = $(this).attr( "data-theVideo" ), 
    videoSRCauto = videoSRC+"?autoplay=1" ;
    $(theModal+' iframe').attr('src', videoSRCauto);
    $(theModal+' button.close').click(function () {
        $(theModal+' iframe').attr('src', videoSRC);
    });   
  });
}

THE FUNCTION CALL:

$(document).ready(function(){
  autoPlayYouTubeModal();
});

The FIDDLE: http://jsfiddle.net/jeremykenedy/h8daS/1/

Inversion of Control vs Dependency Injection

IoC - Inversion of control is generic term, independent of language, it is actually not create the objects but describe in which fashion object is being created.

DI - Dependency Injection is concrete term, in which we provide dependencies of the object at run time by using different injection techniques viz. Setter Injection, Constructor Injection or by Interface Injection.

ReactJS map through Object

I am not sure why Aleksey Potapov marked the answer for deletion but it did solve my problem. Using Object.keys(subjects).map gave me an array of strings containing the name of each object, while Object.entries(subjects).map gave me an array with all data inside witch it's what I wanted being able to do this:

const dataInfected = Object.entries(dataDay).map((day, i) => {
    console.log(day[1].confirmed);
});

I hope it helps the owner of the post or someone else passing by.

str_replace with array

Because str_replace() replaces left to right, it might replace a previously inserted value when doing multiple replacements.

    // Outputs F because A is replaced with B, then B is replaced with C, and so on...
    // Finally E is replaced with F, because of left to right replacements.
    $search  = array('A', 'B', 'C', 'D', 'E');
    $replace = array('B', 'C', 'D', 'E', 'F');
    $subject = 'A';
    echo str_replace($search, $replace, $subject);

Close virtual keyboard on button press

Use Below Code

your_button_id.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        try  {
            InputMethodManager imm = (InputMethodManager)getSystemService(INPUT_METHOD_SERVICE);
            imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 0);
        } catch (Exception e) {

        }
    }
});

Oracle SQL: Update a table with data from another table

Update table set column = (select...)

never worked for me since set only expects 1 value - SQL Error: ORA-01427: single-row subquery returns more than one row.

here's the solution:

BEGIN
For i in (select id, name, desc from table1) 
LOOP
Update table2 set name = i.name, desc = i.desc where id = i.id;
END LOOP;
END;

That's how exactly you run it on SQLDeveloper worksheet. They say it's slow but that's the only solution that worked for me on this case.

How to do what head, tail, more, less, sed do in Powershell?

$Push_Pop = $ErrorActionPreference #Suppresses errors
$ErrorActionPreference = “SilentlyContinue” #Suppresses errors
#Script
    #gc .\output\*.csv -ReadCount 5 | %{$_;throw "pipeline end!"} # head
    #gc .\output\*.csv | %{$num=0;}{$num++;"$num $_"}             # cat -n
    gc .\output\*.csv | %{$num=0;}{$num++; if($num -gt 2 -and $num -lt 7){"$num $_"}} # sed
#End Script 
$ErrorActionPreference = $Push_Pop #Suppresses errors

You don't get all the errors with the pushpop code BTW, your code only works with the "sed" option. All the rest ignores anything but gc and path.

DateTime.TryParse issue with dates of yyyy-dd-MM format

Try using safe TryParseExact method

DateTime temp;
string   date = "2011-29-01 12:00 am";

DateTime.TryParseExact(date, "yyyy-dd-MM hh:mm tt", CultureInfo.InvariantCulture, DateTimeStyles.None, out temp);

How to extract text from a PDF?

On my Macintosh systems, I find that "Adobe Reader" does a reasonably good job. I created an alias on my Desktop that points to the "Adobe Reader.app", and all I do is drop a pdf-file on the alias, which makes it the active document in Adobe Reader, and then from the File-menu, I choose "Save as Text...", give it a name and where to save it, click "Save", and I'm done.

Embedding a media player in a website using HTML

<html>

<head>
  <H1>
      Automatically play music files on your website when a page loads
    </H1>
</head>

<body>
  <embed src="YourMusic.mp3" autostart="true" loop="true" width="2" height="0">
  </embed>
</body>

</html>

Deploying just HTML, CSS webpage to Tomcat

If you want to create a .war file you can deploy to a Tomcat instance using the Manager app, create a folder, put all your files in that folder (including an index.html file) move your terminal window into that folder, and execute the following command:

zip -r <AppName>.war *

I've tested it with Tomcat 8 on the Mac, but it should work anywhere

Sleep function in C++

Use std::this_thread::sleep_for:

#include <chrono>
#include <thread>

std::chrono::milliseconds timespan(111605); // or whatever

std::this_thread::sleep_for(timespan);

There is also the complementary std::this_thread::sleep_until.


Prior to C++11, C++ had no thread concept and no sleep capability, so your solution was necessarily platform dependent. Here's a snippet that defines a sleep function for Windows or Unix:

#ifdef _WIN32
    #include <windows.h>

    void sleep(unsigned milliseconds)
    {
        Sleep(milliseconds);
    }
#else
    #include <unistd.h>
    
    void sleep(unsigned milliseconds)
    {
        usleep(milliseconds * 1000); // takes microseconds
    }
#endif

But a much simpler pre-C++11 method is to use boost::this_thread::sleep.

Why is processing a sorted array faster than processing an unsorted array?

You are a victim of branch prediction fail.


What is Branch Prediction?

Consider a railroad junction:

Image showing a railroad junction Image by Mecanismo, via Wikimedia Commons. Used under the CC-By-SA 3.0 license.

Now for the sake of argument, suppose this is back in the 1800s - before long distance or radio communication.

You are the operator of a junction and you hear a train coming. You have no idea which way it is supposed to go. You stop the train to ask the driver which direction they want. And then you set the switch appropriately.

Trains are heavy and have a lot of inertia. So they take forever to start up and slow down.

Is there a better way? You guess which direction the train will go!

  • If you guessed right, it continues on.
  • If you guessed wrong, the captain will stop, back up, and yell at you to flip the switch. Then it can restart down the other path.

If you guess right every time, the train will never have to stop.
If you guess wrong too often, the train will spend a lot of time stopping, backing up, and restarting.


Consider an if-statement: At the processor level, it is a branch instruction:

Screenshot of compiled code containing an if statement

You are a processor and you see a branch. You have no idea which way it will go. What do you do? You halt execution and wait until the previous instructions are complete. Then you continue down the correct path.

Modern processors are complicated and have long pipelines. So they take forever to "warm up" and "slow down".

Is there a better way? You guess which direction the branch will go!

  • If you guessed right, you continue executing.
  • If you guessed wrong, you need to flush the pipeline and roll back to the branch. Then you can restart down the other path.

If you guess right every time, the execution will never have to stop.
If you guess wrong too often, you spend a lot of time stalling, rolling back, and restarting.


This is branch prediction. I admit it's not the best analogy since the train could just signal the direction with a flag. But in computers, the processor doesn't know which direction a branch will go until the last moment.

So how would you strategically guess to minimize the number of times that the train must back up and go down the other path? You look at the past history! If the train goes left 99% of the time, then you guess left. If it alternates, then you alternate your guesses. If it goes one way every three times, you guess the same...

In other words, you try to identify a pattern and follow it. This is more or less how branch predictors work.

Most applications have well-behaved branches. So modern branch predictors will typically achieve >90% hit rates. But when faced with unpredictable branches with no recognizable patterns, branch predictors are virtually useless.

Further reading: "Branch predictor" article on Wikipedia.


As hinted from above, the culprit is this if-statement:

if (data[c] >= 128)
    sum += data[c];

Notice that the data is evenly distributed between 0 and 255. When the data is sorted, roughly the first half of the iterations will not enter the if-statement. After that, they will all enter the if-statement.

This is very friendly to the branch predictor since the branch consecutively goes the same direction many times. Even a simple saturating counter will correctly predict the branch except for the few iterations after it switches direction.

Quick visualization:

T = branch taken
N = branch not taken

data[] = 0, 1, 2, 3, 4, ... 126, 127, 128, 129, 130, ... 250, 251, 252, ...
branch = N  N  N  N  N  ...   N    N    T    T    T  ...   T    T    T  ...

       = NNNNNNNNNNNN ... NNNNNNNTTTTTTTTT ... TTTTTTTTTT  (easy to predict)

However, when the data is completely random, the branch predictor is rendered useless, because it can't predict random data. Thus there will probably be around 50% misprediction (no better than random guessing).

data[] = 226, 185, 125, 158, 198, 144, 217, 79, 202, 118,  14, 150, 177, 182, ...
branch =   T,   T,   N,   T,   T,   T,   T,  N,   T,   N,   N,   T,   T,   T  ...

       = TTNTTTTNTNNTTT ...   (completely random - impossible to predict)

So what can be done?

If the compiler isn't able to optimize the branch into a conditional move, you can try some hacks if you are willing to sacrifice readability for performance.

Replace:

if (data[c] >= 128)
    sum += data[c];

with:

int t = (data[c] - 128) >> 31;
sum += ~t & data[c];

This eliminates the branch and replaces it with some bitwise operations.

(Note that this hack is not strictly equivalent to the original if-statement. But in this case, it's valid for all the input values of data[].)

Benchmarks: Core i7 920 @ 3.5 GHz

C++ - Visual Studio 2010 - x64 Release

Scenario Time (seconds)
Branching - Random data 11.777
Branching - Sorted data 2.352
Branchless - Random data 2.564
Branchless - Sorted data 2.587

Java - NetBeans 7.1.1 JDK 7 - x64

Scenario Time (seconds)
Branching - Random data 10.93293813
Branching - Sorted data 5.643797077
Branchless - Random data 3.113581453
Branchless - Sorted data 3.186068823

Observations:

  • With the Branch: There is a huge difference between the sorted and unsorted data.
  • With the Hack: There is no difference between sorted and unsorted data.
  • In the C++ case, the hack is actually a tad slower than with the branch when the data is sorted.

A general rule of thumb is to avoid data-dependent branching in critical loops (such as in this example).


Update:

  • GCC 4.6.1 with -O3 or -ftree-vectorize on x64 is able to generate a conditional move. So there is no difference between the sorted and unsorted data - both are fast.

    (Or somewhat fast: for the already-sorted case, cmov can be slower especially if GCC puts it on the critical path instead of just add, especially on Intel before Broadwell where cmov has 2 cycle latency: gcc optimization flag -O3 makes code slower than -O2)

  • VC++ 2010 is unable to generate conditional moves for this branch even under /Ox.

  • Intel C++ Compiler (ICC) 11 does something miraculous. It interchanges the two loops, thereby hoisting the unpredictable branch to the outer loop. So not only is it immune to the mispredictions, it is also twice as fast as whatever VC++ and GCC can generate! In other words, ICC took advantage of the test-loop to defeat the benchmark...

  • If you give the Intel compiler the branchless code, it just out-right vectorizes it... and is just as fast as with the branch (with the loop interchange).

This goes to show that even mature modern compilers can vary wildly in their ability to optimize code...

Round up value to nearest whole number in SQL UPDATE

Combine round and ceiling to get a proper round up.

select ceiling(round(984.375000), 0)) => 984

while

select round(984.375000, 0) => 984.000000

and

select ceil (984.375000) => 985

SQL - IF EXISTS UPDATE ELSE INSERT Syntax Error

You have to add THEN

IF EXISTS(SELECT * FROM component_psar WHERE tbl_id = '2' AND row_nr = '1') 
THEN
UPDATE component_psar SET col_1 = '1', col_2 = '1', col_3 = '1', col_4 = '1', col_5 = '1', col_6 = '1', unit = '1', add_info = '1', fsar_lock = '1' WHERE tbl_id = '2' AND row_nr = '1' 
ELSE 
INSERT INTO component_psar (tbl_id, row_nr, col_1, col_2, col_3, col_4, col_5, col_6, unit, add_info, fsar_lock) VALUES('2', '1', '1', '1', '1', '1', '1', '1', '1', '1', 'N')

What is the => assignment in C# in a property signature

For the following statement shared by Alex Booker in their answer

When the compiler encounters an expression-bodied property member, it essentially converts it to a getter like this:

Please see the following screenshot, it shows how this statement (using SharpLab link)

public string APIBasePath => Configuration.ToolsAPIBasePath;

converts to

public string APIBasePath
{
    get
    {
        return Configuration.ToolsAPIBasePath;
    }
}

Screenshot: enter image description here

What's the most efficient way to test two integer ranges for overlap?

My case is different. i want check two time ranges overlap. there should not be a unit time overlap. here is Go implementation.

    func CheckRange(as, ae, bs, be int) bool {
    return (as >= be) != (ae > bs)
    }

Test cases

if CheckRange(2, 8, 2, 4) != true {
        t.Error("Expected 2,8,2,4 to equal TRUE")
    }

    if CheckRange(2, 8, 2, 4) != true {
        t.Error("Expected 2,8,2,4 to equal TRUE")
    }

    if CheckRange(2, 8, 6, 9) != true {
        t.Error("Expected 2,8,6,9 to equal TRUE")
    }

    if CheckRange(2, 8, 8, 9) != false {
        t.Error("Expected 2,8,8,9 to equal FALSE")
    }

    if CheckRange(2, 8, 4, 6) != true {
        t.Error("Expected 2,8,4,6 to equal TRUE")
    }

    if CheckRange(2, 8, 1, 9) != true {
        t.Error("Expected 2,8,1,9 to equal TRUE")
    }

    if CheckRange(4, 8, 1, 3) != false {
        t.Error("Expected 4,8,1,3 to equal FALSE")
    }

    if CheckRange(4, 8, 1, 4) != false {
        t.Error("Expected 4,8,1,4 to equal FALSE")
    }

    if CheckRange(2, 5, 6, 9) != false {
        t.Error("Expected 2,5,6,9 to equal FALSE")
    }

    if CheckRange(2, 5, 5, 9) != false {
        t.Error("Expected 2,5,5,9 to equal FALSE")
    }

you can see there is XOR pattern in boundary comparison

TensorFlow not found using pip

This worked for me with Python 2.7 on Mac OS X Yosemite 10.10.5:

sudo pip install --upgrade https://storage.googleapis.com/tensorflow/mac/tensorflow-0.5.0-py2-none-any.whl

How to embed small icon in UILabel

You could use a UITextField with the leftView property and then set the enabled property to NO

Or use a UIButton and setImage:forControlState

Regex empty string or email

This regex pattern will match an empty string:

^$

And this will match (crudely) an email or an empty string:

(^$|^.*@.*\..*$)

My eclipse won't open, i download the bundle pack it keeps saying error log

Make sure you have the prerequisite, a JVM (http://wiki.eclipse.org/Eclipse/Installation#Install_a_JVM) installed.

This will be a JRE and JDK package.

There are a number of sources which includes: http://www.oracle.com/technetwork/java/javase/downloads/index.html.

How can I refresh or reload the JFrame?

Try

SwingUtilities.updateComponentTreeUI(frame);

If it still doesn't work then after completing the above step try

frame.invalidate();
frame.validate();
frame.repaint();

How to convert a Java 8 Stream to an Array?

If you want to get an array of ints, with values from 1 to 10, from a Stream<Integer>, there is IntStream at your disposal.

Here we create a Stream with a Stream.of method and convert a Stream<Integer> to an IntStream using a mapToInt. Then we can call IntStream's toArray method.

Stream<Integer> stream = Stream.of(1,2,3,4,5,6,7,8,9,10);
//or use this to create our stream 
//Stream<Integer> stream = IntStream.rangeClosed(1, 10).boxed();
int[] array =  stream.mapToInt(x -> x).toArray();

Here is the same thing, without the Stream<Integer>, using only the IntStream:

int[]array2 =  IntStream.rangeClosed(1, 10).toArray();

java : non-static variable cannot be referenced from a static context Error

Your main() method is static, but it is referencing two non-static members: con2 and getConnectionUrl2(). You need to do one of three things:

1) Make con2 and getConnectionUrl2() static.

2) Inside main(), create an instance of class testconnect and access con2 and getConnectionUrl2() off of that.

3) Break out a different class to hold con2 and getConnectionUrl2() so that testconnect only has main in it. It will still need to instantiate the different class and call the methods off that.

Option #3 is the best option. #1 is the worst.

But, you cannot access non-static members from within a static method.

how to delete all cookies of my website in php

make sure you call your setcookie function before any output happens on your site.

also, if your users are logging out, you should also delete/invalidate their session variables.

How to build a DataTable from a DataGridView?

First convert you datagridview's data to List, then convert List to DataTable

        public static DataTable ToDataTable<T>( this List<T> list) where T : class {
        Type type = typeof(T);
        var ps = type.GetProperties ( );
        var cols = from p in ps
                   select new DataColumn ( p.Name , p.PropertyType );

        DataTable dt = new DataTable();
        dt.Columns.AddRange(cols.ToArray());

        list.ForEach ( (l) => {
            List<object> objs = new List<object>();
            objs.AddRange ( ps.Select ( p => p.GetValue ( l , null ) ) );
            dt.Rows.Add ( objs.ToArray ( ) );
        } );

        return dt;
    }

How to AUTO_INCREMENT in db2?

hi If you are still not able to make column as AUTO_INCREMENT while creating table. As a work around first create table that is:

create table student( sid integer NOT NULL sname varchar(30), PRIMARY KEY (sid) );

and then explicitly try to alter column bu using the following

alter table student alter column sid set GENERATED BY DEFAULT AS IDENTITY

Or

alter table student alter column sid set GENERATED BY DEFAULT AS IDENTITY (start with 100)

Check if list is empty in C#

gridview itself has a method that checks if the datasource you are binding it to is empty, it lets you display something else.

Tooltips for cells in HTML table (no Javascript)

have you tried?

<td title="This is Title">

its working fine here on Firefox v 18 (Aurora), Internet Explorer 8 & Google Chrome v 23x

How to get the date from the DatePicker widget in Android?

I manged to set the MinDate & the MaxDate programmatically like this :

    final Calendar c = Calendar.getInstance();

    int maxYear = c.get(Calendar.YEAR) - 20; // this year ( 2011 ) - 20 = 1991
    int maxMonth = c.get(Calendar.MONTH);
    int maxDay = c.get(Calendar.DAY_OF_MONTH);

    int minYear = 1960;
    int minMonth = 0; // january
    int minDay = 25;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.create_account);
        BirthDateDP = (DatePicker) findViewById(R.id.create_account_BirthDate_DatePicker);
        BirthDateDP.init(maxYear - 10, maxMonth, maxDay, new OnDateChangedListener()
        {

        @Override
        public void onDateChanged(DatePicker view, int year, int monthOfYear, int dayOfMonth)
        {
            if (year < minYear)
                view.updateDate(minYear, minMonth, minDay);

                if (monthOfYear < minMonth && year == minYear)
                view.updateDate(minYear, minMonth, minDay);

                if (dayOfMonth < minDay && year == minYear && monthOfYear == minMonth)
                view.updateDate(minYear, minMonth, minDay);


                if (year > maxYear)
                view.updateDate(maxYear, maxMonth, maxDay);

                if (monthOfYear > maxMonth && year == maxYear)
                view.updateDate(maxYear, maxMonth, maxDay);

                if (dayOfMonth > maxDay && year == maxYear && monthOfYear == maxMonth)
                view.updateDate(maxYear, maxMonth, maxDay);
        }}); // BirthDateDP.init()
    } // activity

it works fine for me, enjoy :)

How to add 10 days to current time in Rails

Try this on Ruby. It will return a new date/time the specified number of days in the future

DateTime.now.days_since(10)

Check with jquery if div has overflowing elements

Partially based on Mohsen's answer (the added first condition covers the case where the child is hidden before the parent):

jQuery.fn.isChildOverflowing = function (child) {
  var p = jQuery(this).get(0);
  var el = jQuery(child).get(0);
  return (el.offsetTop < p.offsetTop || el.offsetLeft < p.offsetLeft) ||
    (el.offsetTop + el.offsetHeight > p.offsetTop + p.offsetHeight || el.offsetLeft + el.offsetWidth > p.offsetLeft + p.offsetWidth);
};

Then just do:

jQuery('#parent').isChildOverflowing('#child');

When running WebDriver with Chrome browser, getting message, "Only local connections are allowed" even though browser launches properly

Very often this error appears if you use incompatible versions of Selenium and ChromeDriver.

Selenium 3.0.1 for Maven project:

    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>3.0.1</version>
    </dependency>

ChromeDriver 2.27: https://sites.google.com/a/chromium.org/chromedriver/downloads

How to hide only the Close (x) button?

Well, you can hide it, by removing the entire system menu:

private const int WS_SYSMENU = 0x80000;
protected override CreateParams CreateParams
{
    get
    {
        CreateParams cp = base.CreateParams;
        cp.Style &= ~WS_SYSMENU;
        return cp;
    }
}

Of course, doing so removes the minimize and maximize buttons.

If you keep the system menu but remove the close item then the close button remains but is disabled.

The final alternative is to paint the non-client area yourself. That's pretty hard to get right.

How can I add a table of contents to a Jupyter / JupyterLab notebook?

nbextensions ToC instructions

Introduction

As @Ian and @Sergey have mentioned, nbextensions is a simple solution. To elaborate their answer, here is a few more information.

What is nbextensions?

The nbextensions contains a collection of extensions that add functionality to your Jupyter notebook.

For example, just to cite a few extensions:

  • Table of Contents

  • Collapsible headings

Install nbextensions

The installation can be done through Conda or PIP

# If conda:
conda install -c conda-forge jupyter_contrib_nbextensions
# or with pip:
pip install jupyter_contrib_nbextensions

You will see the new tab Nbextensions in the jupyter notebook menu. Uncheck the checkbox at the top disable configuration for nbextensions without explicit compatibility (they may break your notebook environment, but can be useful to show for nbextension development) and then check Table of Contents(2). That is all. Screenshot:

choice of "Table of Contents(2)" in Configurable nbextensions

Copy js and css files

To copy the nbextensions' javascript and css files into the jupyter server's search directory, do the following:

jupyter contrib nbextension install --user

Toggle extensions

Note that if you are not familiar with the terminal, it would be better to install nbextensions configurator (see the next section)

You can enable/disable the extensions of your choice. As the documentation mentions, the generic command is:

jupyter nbextension enable <nbextension require path>

Concretely, to enable the ToC (Table of Contents) extension, do:

jupyter nbextension enable toc2/main

Install Configuration interface (optional but useful)

As its documentation says, nbextensions_configurator provides config interfaces for nbextensions.

It looks like the following: nbextensions configurators

To install it if you use conda:

conda install -c conda-forge jupyter_nbextensions_configurator

If you don't have Conda or don't want to install through Conda, then do the following 2 steps:

pip install jupyter_nbextensions_configurator
jupyter nbextensions_configurator enable --user

Populating a data frame in R in a loop

You could do it like this:

 iterations = 10
 variables = 2

 output <- matrix(ncol=variables, nrow=iterations)

 for(i in 1:iterations){
  output[i,] <- runif(2)

 }

 output

and then turn it into a data.frame

 output <- data.frame(output)
 class(output)

what this does:

  1. create a matrix with rows and columns according to the expected growth
  2. insert 2 random numbers into the matrix
  3. convert this into a dataframe after the loop has finished.

Make the size of a heatmap bigger with seaborn

You could alter the figsize by passing a tuple showing the width, height parameters you would like to keep.

import matplotlib.pyplot as plt

fig, ax = plt.subplots(figsize=(10,10))         # Sample figsize in inches
sns.heatmap(df1.iloc[:, 1:6:], annot=True, linewidths=.5, ax=ax)

EDIT

I remember answering a similar question of yours where you had to set the index as TIMESTAMP. So, you could then do something like below:

df = df.set_index('TIMESTAMP')
df.resample('30min').mean()
fig, ax = plt.subplots()
ax = sns.heatmap(df.iloc[:, 1:6:], annot=True, linewidths=.5)
ax.set_yticklabels([i.strftime("%Y-%m-%d %H:%M:%S") for i in df.index], rotation=0)

For the head of the dataframe you posted, the plot would look like:

enter image description here

What Regex would capture everything from ' mark to the end of a line?

'.*

I believe you need the option, Multiline.

How to change maven java home

Appears to be a duplicate of https://askubuntu.com/questions/21131/how-to-correctly-remove-openjdk-and-jre-and-set-the-system-use-only-and-only-sun#answer-21137 assuming that you are using Ubuntu.

The key is to use the command sudo update-java-alternatives -s java-6-sun. Any commands that rely on javac will be affected and not just Maven.

maven-dependency-plugin (goals "copy-dependencies", "unpack") is not supported by m2e

It seems to be a known issue. You can instruct m2e to ignore this.

Option 1: pom.xml

Add the following inside your <build/> tag:

<pluginManagement>
<plugins>
    <!-- Ignore/Execute plugin execution -->
    <plugin>
        <groupId>org.eclipse.m2e</groupId>
        <artifactId>lifecycle-mapping</artifactId>
        <version>1.0.0</version>
        <configuration>
            <lifecycleMappingMetadata>
                <pluginExecutions>
                    <!-- copy-dependency plugin -->
                    <pluginExecution>
                        <pluginExecutionFilter>
                            <groupId>org.apache.maven.plugins</groupId>
                            <artifactId>maven-dependency-plugin</artifactId>
                            <versionRange>[1.0.0,)</versionRange>
                            <goals>
                                <goal>copy-dependencies</goal>
                            </goals>
                        </pluginExecutionFilter>
                        <action>
                            <ignore />
                        </action>
                    </pluginExecution>
                </pluginExecutions>
            </lifecycleMappingMetadata>
        </configuration>
    </plugin>
   </plugins></pluginManagement>

You will need to do Maven... -> Update Project Configuration on your project after this.

Read more: http://wiki.eclipse.org/M2E_plugin_execution_not_covered#m2e_maven_plugin_coverage_status

Option 2: Global Eclipse Override

To avoid changing your POM files, the ignore override can be applied to the whole workspace via Eclipse settings.

Save this file somewhere on the disk: https://gist.github.com/maksimov/8906462

In Eclipse/Preferences/Maven/Lifecycle Mappings browse to this file and click OK:

Eclipse Settings

How to create a JSON object

Usually, you would do something like this:

$post_data = json_encode(array('item' => $post_data));

But, as it seems you want the output to be with "{}", you better make sure to force json_encode() to encode as object, by passing the JSON_FORCE_OBJECT constant.

$post_data = json_encode(array('item' => $post_data), JSON_FORCE_OBJECT);

"{}" brackets specify an object and "[]" are used for arrays according to JSON specification.

Read CSV with Scanner()

If you absolutely must use Scanner, then you must set its delimiter via its useDelimiter(...) method. Else it will default to using all white space as its delimiter. Better though as has already been stated -- use a CSV library since this is what they do best.

For example, this delimiter will split on commas with or without surrounding whitespace:

scanner.useDelimiter("\\s*,\\s*");

Please check out the java.util.Scanner API for more on this.

How to change the CHARACTER SET (and COLLATION) throughout a database?

Adding to what David Whittaker posted, I have created a query that generates the complete table and columns alter statement that will convert each table. It may be a good idea to run

SET SESSION group_concat_max_len = 100000;

first to make sure your group concat doesn't go over the very small limit as seen here.

     SELECT a.table_name, concat('ALTER TABLE ', a.table_schema, '.', a.table_name, ' DEFAULT CHARACTER SET utf8mb4 DEFAULT COLLATE utf8mb4_unicode_ci, ',
        group_concat(distinct(concat(' MODIFY ',  column_name, ' ', column_type, ' CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci ', if (is_nullable = 'NO', ' NOT', ''), ' NULL ',
        if (COLUMN_DEFAULT is not null, CONCAT(' DEFAULT \'', COLUMN_DEFAULT, '\''), ''), if (EXTRA != '', CONCAT(' ', EXTRA), '')))), ';') as alter_statement
    FROM information_schema.columns a
    INNER JOIN INFORMATION_SCHEMA.TABLES b ON a.TABLE_CATALOG = b.TABLE_CATALOG
        AND a.TABLE_SCHEMA = b.TABLE_SCHEMA
        AND a.TABLE_NAME = b.TABLE_NAME
        AND b.table_type != 'view'
    WHERE a.table_schema = ? and (collation_name = 'latin1_swedish_ci' or collation_name = 'utf8mb4_general_ci')
    GROUP BY table_name;

A difference here between the previous answer is it was using utf8 instead of ut8mb4 and using t1.data_type with t1.CHARACTER_MAXIMUM_LENGTH didn't work for enums. Also, my query excludes views since those will have to altered separately.

I simply used a Perl script to return all these alters as an array and iterated over them, fixed the columns that were too long (generally they were varchar(256) when the data generally only had 20 characters in them so that was an easy fix).

I found some data was corrupted when altering from latin1 -> utf8mb4. It appeared to be utf8 encoded latin1 characters in columns would get goofed in the conversion. I simply held data from the columns I knew was going to be an issue in memory from before and after the alter and compared them and generated update statements to fix the data.

How to show another window from mainwindow in QT

  1. Implement a slot in your QMainWindow where you will open your new Window,
  2. Place a widget on your QMainWindow,
  3. Connect a signal from this widget to a slot from the QMainWindow (for example: if the widget is a QPushButton connect the signal click() to the QMainWindow custom slot you have created).

Code example:

MainWindow.h

// ...
include "newwindow.h"
// ...
public slots:
   void openNewWindow();
// ...
private:
   NewWindow *mMyNewWindow;
// ...
}

MainWindow.cpp

// ...
   MainWindow::MainWindow()
   {
      // ...
      connect(mMyButton, SIGNAL(click()), this, SLOT(openNewWindow()));
      // ...
   }
// ...
void MainWindow::openNewWindow()
{
   mMyNewWindow = new NewWindow(); // Be sure to destroy your window somewhere
   mMyNewWindow->show();
   // ...
}

This is an example on how display a custom new window. There are a lot of ways to do this.

Java Could not reserve enough space for object heap error

I had this problem. I solved it with downloading 64x of the Java. Here is the link: http://javadl.sun.com/webapps/download/AutoDL?BundleId=87443

Sending "User-agent" using Requests library in Python

The user-agent should be specified as a field in the header.

Here is a list of HTTP header fields, and you'd probably be interested in request-specific fields, which includes User-Agent.

If you're using requests v2.13 and newer

The simplest way to do what you want is to create a dictionary and specify your headers directly, like so:

import requests

url = 'SOME URL'

headers = {
    'User-Agent': 'My User Agent 1.0',
    'From': '[email protected]'  # This is another valid field
}

response = requests.get(url, headers=headers)

If you're using requests v2.12.x and older

Older versions of requests clobbered default headers, so you'd want to do the following to preserve default headers and then add your own to them.

import requests

url = 'SOME URL'

# Get a copy of the default headers that requests would use
headers = requests.utils.default_headers()

# Update the headers with your custom ones
# You don't have to worry about case-sensitivity with
# the dictionary keys, because default_headers uses a custom
# CaseInsensitiveDict implementation within requests' source code.
headers.update(
    {
        'User-Agent': 'My User Agent 1.0',
    }
)

response = requests.get(url, headers=headers)

What is the use of printStackTrace() method in Java?

printStackTrace() helps the programmer to understand where the actual problem occurred. It helps to trace the exception. it is printStackTrace() method of Throwable class inherited by every exception class. This method prints the same message of e object and also the line number where the exception occurred.

The following is an another example of print stack of the Exception in Java.

public class Demo {
   public static void main(String[] args) {
      try {
         ExceptionFunc();
      } catch(Throwable e) {
         e.printStackTrace();
      }
   }
   public static void ExceptionFunc() throws Throwable {
      Throwable t = new Throwable("This is new Exception in Java...");

      StackTraceElement[] trace = new StackTraceElement[] {
         new StackTraceElement("ClassName","methodName","fileName",5)
      };
      t.setStackTrace(trace);
      throw t;
   }
}

java.lang.Throwable: This is new Exception in Java... at ClassName.methodName(fileName:5)

How can I connect to a Tor hidden service using cURL in PHP?

Try to add this:

curl_setopt($ch, CURLOPT_HEADER, 1); 
curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1); 

Switch case in C# - a constant value is expected

Johnnie, Please go through msdn guide on switch. Also, the C# language specification clearly defines the compile time error case:

• If the type of the switch expression is sbyte, byte, short, ushort, int, uint, long, ulong, bool, char, string, or an enum-type, or if it is the nullable type corresponding to one of these types, then that is the governing type of the switch statement.

• Otherwise, exactly one user-defined implicit conversion (§6.4) must exist from the type of the switch expression to one of the following possible governing types: sbyte, byte, short, ushort, int, uint, long, ulong, char, string, or, a nullable type corresponding to one of those types.

• Otherwise, if no such implicit conversion exists, or if more than one such implicit conversion exists, a compile-time error occurs.

Hope this helps.

Conditionally ignoring tests in JUnit 4

A quick note: Assume.assumeTrue(condition) ignores rest of the steps but passes the test. To fail the test, use org.junit.Assert.fail() inside the conditional statement. Works same like Assume.assumeTrue() but fails the test.

How can I split a string into segments of n characters?

_x000D_
_x000D_
var str = 'abcdefghijkl';_x000D_
console.log(str.match(/.{1,3}/g));
_x000D_
_x000D_
_x000D_

Note: Use {1,3} instead of just {3} to include the remainder for string lengths that aren't a multiple of 3, e.g:

_x000D_
_x000D_
console.log("abcd".match(/.{1,3}/g)); // ["abc", "d"]
_x000D_
_x000D_
_x000D_


A couple more subtleties:

  1. If your string may contain newlines (which you want to count as a character rather than splitting the string), then the . won't capture those. Use /[\s\S]{1,3}/ instead. (Thanks @Mike).
  2. If your string is empty, then match() will return null when you may be expecting an empty array. Protect against this by appending || [].

So you may end up with:

_x000D_
_x000D_
var str = 'abcdef \t\r\nghijkl';_x000D_
var parts = str.match(/[\s\S]{1,3}/g) || [];_x000D_
console.log(parts);_x000D_
_x000D_
console.log(''.match(/[\s\S]{1,3}/g) || []);
_x000D_
_x000D_
_x000D_

Creating an R dataframe row-by-row

This is a silly example of how to use do.call(rbind,) on the output of Map() [which is similar to lapply()]

> DF <- do.call(rbind,Map(function(x) data.frame(a=x,b=x+1),x=1:3))
> DF
  x y
1 1 2
2 2 3
3 3 4
> class(DF)
[1] "data.frame"

I use this construct quite often.

How to interpret "loss" and "accuracy" for a machine learning model

Just to clarify the Training/Validation/Test data sets: The training set is used to perform the initial training of the model, initializing the weights of the neural network.

The validation set is used after the neural network has been trained. It is used for tuning the network's hyperparameters, and comparing how changes to them affect the predictive accuracy of the model. Whereas the training set can be thought of as being used to build the neural network's gate weights, the validation set allows fine tuning of the parameters or architecture of the neural network model. It's useful as it allows repeatable comparison of these different parameters/architectures against the same data and networks weights, to observe how parameter/architecture changes affect the predictive power of the network.

Then the test set is used only to test the predictive accuracy of the trained neural network on previously unseen data, after training and parameter/architecture selection with the training and validation data sets.

MySQLi count(*) always returns 1

I find this way more readable:

$result = $mysqli->query('select count(*) as `c` from `table`');
$count = $result->fetch_object()->c;
echo "there are {$count} rows in the table";

Not that I have anything against arrays...

Node.js check if path is file or directory

Seriously, question exists five years and no nice facade?

function is_dir(path) {
    try {
        var stat = fs.lstatSync(path);
        return stat.isDirectory();
    } catch (e) {
        // lstatSync throws an error if path doesn't exist
        return false;
    }
}

How do I uniquely identify computers visiting my web site?

A possibility is using flash cookies:

  • Ubiquitous availability (95 percent of visitors will probably have flash)
  • You can store more data per cookie (up to 100 KB)
  • Shared across browsers, so more likely to uniquely identify a machine
  • Clearing the browser cookies does not remove the flash cookies.

You'll need to build a small (hidden) flash movie to read and write them.

Whatever route you pick, make sure your users opt IN to being tracked, otherwise you're invading their privacy and become one of the bad guys.

Replace CRLF using powershell

Alternative solution that won't append a spurious CR-LF:

$original_file ='C:\Users\abc\Desktop\File\abc.txt'
$text = [IO.File]::ReadAllText($original_file) -replace "`r`n", "`n"
[IO.File]::WriteAllText($original_file, $text)

Get everything after the dash in a string in JavaScript

AFAIK, both substring() and indexOf() are supported by both Mozilla and IE. However, note that substr() might not be supported on earlier versions of some browsers (esp. Netscape/Opera).

Your post indicates that you already know how to do it using substring() and indexOf(), so I'm not posting a code sample.

How to use GROUP BY to concatenate strings in SQL Server?

This kind of question is asked here very often, and the solution is going to depend a lot on the underlying requirements:

https://stackoverflow.com/search?q=sql+pivot

and

https://stackoverflow.com/search?q=sql+concatenate

Typically, there is no SQL-only way to do this without either dynamic sql, a user-defined function, or a cursor.

XMLHttpRequest status 0 (responseText is empty)

To see what the problem is, when you get the cryptic error 0 go to ... | More Tools | Developer Tools (Ctrl+Shift+I) in Chrome (on the page giving the error)

Read the red text in the log to get the true error message. If there is too much in there, right-click and Clear Console, then do your last request again.

My first problem was, I was passing in Authorization headers to my own cross-domain web service for the browser for the first time.

I already had:

Access-Control-Allow-Origin: *

But not:

Access-Control-Allow-Methods: GET, POST, PUT, DELETE
Access-Control-Allow-Headers: Authorization

in the response header of my web service.

After I added that, my error zero was gone from my own web server, as well as when running the index.html file locally without a web server, but was still giving errors in code pen.

Back to ... | More Tools | Developer Tools while getting the error in codepen, and there is clearly explained: codepen uses https, so I cannot make calls to http, as the security is lower.

I need to therefore host my web service on https.

Knowing how to get the true error message - priceless!

Array Length in Java

int[] arr = new int[10];

arr is an int type array which has size 10. It is an array of 10 elements. If we don't initialize an array by default array elements contains default value. In case of int array default value is 0.

length is a property which is applicable for an array.
here arr.length will give 10.

How can I add new item to the String array?

You can't. A Java array has a fixed length. If you need a resizable array, use a java.util.ArrayList<String>.

BTW, your code is invalid: you don't initialize the array before using it.

Git: "Corrupt loose object"

I solved this way: I decided to simply copy the uncorrupted object file from the backup's clone to my original repository. This worked just as well. (By the way: If you can't find the object in .git/objects/ by its name, it probably has been [packed][pack] to conserve space.)

Simplest way to download and unzip files in Node.js cross-platform?

yauzl is a robust library for unzipping. Design principles:

  • Follow the spec. Don't scan for local file headers. Read the central directory for file metadata.
  • Don't block the JavaScript thread. Use and provide async APIs.
  • Keep memory usage under control. Don't attempt to buffer entire files in RAM at once.
  • Never crash (if used properly). Don't let malformed zip files bring down client applications who are trying to catch errors.
  • Catch unsafe filenames entries. A zip file entry throws an error if its file name starts with "/" or /[A-Za-z]:// or if it contains ".." path segments or "\" (per the spec).

Currently has 97% test coverage.

Google Maps JS API v3 - Simple Multiple Marker Example

This is the working example map image

var arr = new Array();
    function initialize() { 
        var i;  
        var Locations = [
                {
                  lat:48.856614, 
                  lon:2.3522219000000177, 
                  address:'Paris',
                  gval:'25.5',
                  aType:'Non-Commodity',
                  title:'Paris',
                  descr:'Paris'           
                },        
                    {
                  lat: 55.7512419, 
                  lon: 37.6184217,
                  address:'Moscow',
                  gval:'11.5',
                  aType:'Non-Commodity',
                  title:'Moscow',
                  descr:'Moscow Airport'              
                },     

                {
              lat:-9.481553000000002, 
              lon:147.190242, 
              address:'Port Moresby',
              gval:'1',
              aType:'Oil',
              title:'Papua New Guinea',
              descr:'Papua New Guinea 123123123'              
            },
            {
           lat:20.5200,
           lon:77.7500,
           address:'Indore',
            gval:'1',
            aType:'Oil',
            title:'Indore, India',
            descr:'Airport India'
        }
    ];

    var myOptions = {
        zoom: 2,
        center: new google.maps.LatLng(51.9000,8.4731),
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };

    var map = new google.maps.Map(document.getElementById("map"), myOptions);

    var infowindow =  new google.maps.InfoWindow({
        content: ''
    });

    for (i = 0; i < Locations.length; i++) {
            size=15;        
            var img=new google.maps.MarkerImage('marker.png',           
                new google.maps.Size(size, size),
                new google.maps.Point(0,0),
                new google.maps.Point(size/2, size/2)
           );

        var marker = new google.maps.Marker({
            map: map,
            title: Locations[i].title,
            position: new google.maps.LatLng(Locations[i].lat, Locations[i].lon),           
                icon: img
        });

        bindInfoWindow(marker, map, infowindow, "<p>" + Locations[i].descr + "</p>",Locations[i].title);  

    }

}

function bindInfoWindow(marker, map, infowindow, html, Ltitle) { 
    google.maps.event.addListener(marker, 'mouseover', function() {
            infowindow.setContent(html); 
            infowindow.open(map, marker); 

    });
    google.maps.event.addListener(marker, 'mouseout', function() {
        infowindow.close();

    }); 
} 

Full working example. You can just copy, paste and use.

Gradle: How to Display Test Results in the Console in Real Time?

As stefanglase answered:

adding the following code to your build.gradle (since version 1.1) works fine for output on passed, skipped and failed tests.

test {
    testLogging {
        events "passed", "skipped", "failed", "standardOut", "standardError"
    }
}

What I want to say additionally (I found out this is a problem for starters) is that the gradle test command executes the test only one time per change.

So if you are running it the second time there will be no output on test results. You can also see this in the building output: gradle then says UP-TO-DATE on tests. So its not executed a n-th time.

Smart gradle!

If you want to force the test cases to run, use gradle cleanTest test.

This is slightly off topic but I hope it will help some newbies.

edit

As sparc_spread stated in the comments:

If you want to force gradle to always run fresh tests (which might not always be a good idea) you can add outputs.upToDateWhen {false} to testLogging { [...] }. Continue reading here.

Peace.

Delete with "Join" in Oracle sql Query

Use a subquery in the where clause. For a delete query requirig a join, this example will delete rows that are unmatched in the joined table "docx_document" and that have a create date > 120 days in the "docs_documents" table.

delete from docs_documents d
where d.id in (
    select a.id from docs_documents a
    left join docx_document b on b.id = a.document_id
    where b.id is null
        and floor(sysdate - a.create_date) > 120
 );

How to read response headers in angularjs?

Use the headers variable in success and error callbacks

From documentation.

$http.get('/someUrl').
  success(function(data, status, headers, config) {
    // this callback will be called asynchronously
    // when the response is available
  })
  .error(function(data, status, headers, config) {
    // called asynchronously if an error occurs
    // or server returns response with an error status.
  });

If you are on the same domain, you should be able to retrieve the response headers back. If cross-domain, you will need to add Access-Control-Expose-Headers header on the server.

Access-Control-Expose-Headers: content-type, cache, ...

Unable to load script from assets index.android.bundle on windows

Using npm version 4.3.0 react-native-cli version 2.01 react-native version 0.49.5

In the project directory,

  • mkdir android/app/src/main/assets
  • react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res
  • react-native run-android

The file name has changed from index.android.js to index.js

Count items in a folder with PowerShell

You should use Measure-Object to count things. In this case it would look like:

Write-Host ( Get-ChildItem c:\MyFolder | Measure-Object ).Count;

or if that's too long

Write-Host ( dir c:\MyFolder | mo).Count;

and in PowerShell 4.0 use the measure alias instead of mo

Write-Host (dir c:\MyFolder | measure).Count;

How to Set user name and Password of phpmyadmin

You can simply open the phpmyadmin page from your browser, then open any existing database -> go to Privileges tab, click on your root user and then a popup window will appear, you can set your password there.. Hope this Helps.

How do you create a dropdownlist from an enum in ASP.NET MVC?

For MVC v5.1 use Html.EnumDropDownListFor

@Html.EnumDropDownListFor(
    x => x.YourEnumField,
    "Select My Type", 
    new { @class = "form-control" })

For MVC v5 use EnumHelper

@Html.DropDownList("MyType", 
   EnumHelper.GetSelectList(typeof(MyType)) , 
   "Select My Type", 
   new { @class = "form-control" })

For MVC 5 and lower

I rolled Rune's answer into an extension method:

namespace MyApp.Common
{
    public static class MyExtensions{
        public static SelectList ToSelectList<TEnum>(this TEnum enumObj)
            where TEnum : struct, IComparable, IFormattable, IConvertible
        {
            var values = from TEnum e in Enum.GetValues(typeof(TEnum))
                select new { Id = e, Name = e.ToString() };
            return new SelectList(values, "Id", "Name", enumObj);
        }
    }
}

This allows you to write:

ViewData["taskStatus"] = task.Status.ToSelectList();

by using MyApp.Common

Eclipse - Unable to install breakpoint due to missing line number attributes

Once I experienced the same error when I used junit and Mockito, I forgot to add @PrepareForTest for a static class.

Add below code fixed my problem.

@PrepareForTest({XXXXX.class})

Not sure it was the same case.

How to change Windows 10 interface language on Single Language version

You can download language pack and use "Install or Uninstall display languages" wizard. To do this:

  • Press Win+R, paste lpksetup and press Enter
  • Wizard will appear on the screen
  • Click the Install display languages button
  • In the next page of the wizard, click Browse and pick the *.cab file of the MUI language you downloaded
  • Click the Next button to install language

Combine two columns of text in pandas dataframe

def madd(x):
    """Performs element-wise string concatenation with multiple input arrays.

    Args:
        x: iterable of np.array.

    Returns: np.array.
    """
    for i, arr in enumerate(x):
        if type(arr.item(0)) is not str:
            x[i] = x[i].astype(str)
    return reduce(np.core.defchararray.add, x)

For example:

data = list(zip([2000]*4, ['q1', 'q2', 'q3', 'q4']))
df = pd.DataFrame(data=data, columns=['Year', 'quarter'])
df['period'] = madd([df[col].values for col in ['Year', 'quarter']])

df

    Year    quarter period
0   2000    q1  2000q1
1   2000    q2  2000q2
2   2000    q3  2000q3
3   2000    q4  2000q4

TypeError: document.getElementbyId is not a function

JavaScript is case-sensitive. The b in getElementbyId should be capitalized.

var content = document.getElementById("edit").innerHTML;

How to exit an if clause

So here i understand you're trying to break out of the outer if code block

if some_condition:
    ...
    if condition_a:
       # do something
       # and then exit the outer if block
       ...
    if condition_b:
       # do something
       # and then exit the outer if block
# more code here

One way out of this is that you can test for for a false condition in the outer if block, which will then implicitly exit out of the code block, you then use an else block to nest the other ifs to do something

if test_for_false:
    # Exit the code(which is the outer if code)

else:
    if condition_a:
        # Do something

    if condition_b:
        # Do something

Execute external program

This is not right. Here's how you should use Runtime.exec(). You might also try its more modern cousin, ProcessBuilder:

Java Runtime.getRuntime().exec() alternatives

How to use localization in C#

Great answer by F.Mörk. But if you want to update translation, or add new languages once the application is released, you're stuck, because you always have to recompile it to generate the resources.dll.

Here is a solution to manually compile a resource dll. It uses the resgen.exe and al.exe tools (installed with the sdk).

Say you have a Strings.fr.resx resource file, you can compile a resources dll with the following batch:

resgen.exe /compile Strings.fr.resx,WpfRibbonApplication1.Strings.fr.resources 
Al.exe /t:lib /embed:WpfRibbonApplication1.Strings.fr.resources /culture:"fr" /out:"WpfRibbonApplication1.resources.dll"
del WpfRibbonApplication1.Strings.fr.resources
pause

Be sure to keep the original namespace in the file names (here "WpfRibbonApplication1")

Disposing WPF User Controls

An UserControl has a Destructor, why don't you use that?

~MyWpfControl()
    {
        // Dispose of any Disposable items here
    }

How to best display in Terminal a MySQL SELECT returning too many fields?

Using the Windows Command Prompt you can increase the buffer size of the window as much you want to see the number of columns. This depends on the no of columns in the table.

How can I change CSS display none or block property using jQuery?

Use:

$(#id/.class).show()
$(#id/.class).hide()

This one is the best way.

How do I create dynamic variable names inside a loop?

You can use eval() method to declare dynamic variables. But better to use an Array.

for (var i = 0; i < coords.length; ++i) {
    var str ="marker"+ i+" = undefined";
    eval(str);
}

C++ error : terminate called after throwing an instance of 'std::bad_alloc'

The problem in your code is that you can't store the memory address of a local variable (local to a function, for example) in a globlar variable:

RectInvoice rect(vect,im,x, y, w ,h);
this->rectInvoiceVector.push_back(&rect);

There, &rect is a temporary address (stored in the function's activation registry) and will be destroyed when that function end.

The code should create a dynamic variable:

RectInvoice *rect =  new RectInvoice(vect,im,x, y, w ,h);
this->rectInvoiceVector.push_back(rect);

There you are using a heap address that will not be destroyed in the end of the function's execution. Tell me if it worked for you.

Cheers

Wait for a void async method

The best solution is to use async Task. You should avoid async void for several reasons, one of which is composability.

If the method cannot be made to return Task (e.g., it's an event handler), then you can use SemaphoreSlim to have the method signal when it is about to exit. Consider doing this in a finally block.

Add alternating row color to SQL Server Reporting services report

My matrix data had missing values in it, so I wasn't able to get ahmad's solution to work, but this solution worked for me

Basic idea is to create a child group and field on your innermost group containing the color. Then set the color for each cell in the row based on that field's value.

Removing the first 3 characters from a string

Just use substring: "apple".substring(3); will return le

How to select first parent DIV using jQuery?

two of the best options are

$(this).parent("div:first")

$(this).parent().closest('div')

and of course you can find the class attr by

$(this).parent("div:first").attr("class")

$(this).parent().closest('div').attr("class")

Checking to see if one array's elements are in another array in PHP

You can use array_intersect().

$result = !empty(array_intersect($people, $criminals));

nginx upload client_max_body_size issue

Does your upload die at the very end? 99% before crashing? Client body and buffers are key because nginx must buffer incoming data. The body configs (data of the request body) specify how nginx handles the bulk flow of binary data from multi-part-form clients into your app's logic.

The clean setting frees up memory and consumption limits by instructing nginx to store incoming buffer in a file and then clean this file later from disk by deleting it.

Set body_in_file_only to clean and adjust buffers for the client_max_body_size. The original question's config already had sendfile on, increase timeouts too. I use the settings below to fix this, appropriate across your local config, server, & http contexts.

client_body_in_file_only clean;
client_body_buffer_size 32K;

client_max_body_size 300M;

sendfile on;
send_timeout 300s;

How do I load the contents of a text file into a javascript variable?

If your input was structured as XML, you could use the importXML function. (More info here at quirksmode).

If it isn't XML, and there isn't an equivalent function for importing plain text, then you could open it in a hidden iframe and then read the contents from there.

How to wait till the response comes from the $http request, in angularjs?

for people new to this you can also use a callback for example:

In your service:

.factory('DataHandler',function ($http){

   var GetRandomArtists = function(data, callback){
     $http.post(URL, data).success(function (response) {
         callback(response);
      });
   } 
})

In your controller:

    DataHandler.GetRandomArtists(3, function(response){
      $scope.data.random_artists = response;
   });

Get ALL User Friends Using Facebook Graph API - Android

In v2.0 of the Graph API, calling /me/friends returns the person's friends who also use the app.

In addition, in v2.0, you must request the user_friends permission from each user. user_friends is no longer included by default in every login. Each user must grant the user_friends permission in order to appear in the response to /me/friends. See the Facebook upgrade guide for more detailed information, or review the summary below.

The /me/friendlists endpoint and user_friendlists permission are not what you're after. This endpoint does not return the users friends - its lets you access the lists a person has made to organize their friends. It does not return the friends in each of these lists. This API and permission is useful to allow you to render a custom privacy selector when giving people the opportunity to publish back to Facebook.

If you want to access a list of non-app-using friends, there are two options:

  1. If you want to let your people tag their friends in stories that they publish to Facebook using your App, you can use the /me/taggable_friends API. Use of this endpoint requires review by Facebook and should only be used for the case where you're rendering a list of friends in order to let the user tag them in a post.

  2. If your App is a Game AND your Game supports Facebook Canvas, you can use the /me/invitable_friends endpoint in order to render a custom invite dialog, then pass the tokens returned by this API to the standard Requests Dialog.

In other cases, apps are no longer able to retrieve the full list of a user's friends (only those friends who have specifically authorized your app using the user_friends permission).

For apps wanting allow people to invite friends to use an app, you can still use the Send Dialog on Web or the new Message Dialog on iOS and Android.

How to get current language code with Swift?

This is what I use in Swift 5 Xcode 11:

Inside the class variables:

let languagePrefix = Bundle.main.preferredLocalizations.first?.prefix(2)

This comes as a string. It returns 2 characters, i.e. "en", "es", "de"...

From this I can easily determine what language to display:

 if languagePrefix == "es" { self.flipCard.setTitle("última carta", for: .normal) }
 if languagePrefix == "en" { self.flipCard.setTitle("Last Card", for: .normal) }

If you want the full information of the language, then remove ?.prefex(2)

R: Print list to a text file

depending on your tastes, an alternative to nico's answer:

d<-lapply(mylist, write, file=" ... ", append=T);

How to make Twitter bootstrap modal full screen

The chosen solution does not preserve the round corner style. To preserve the round corners, you should reduce the width and height a little bit and remove the border radius 0. Also it doesn't show the vertical scroll bar...

.modal-dialog {
  width: 98%;
  height: 92%;
  padding: 0;
}

.modal-content {
  height: 99%;
}

How to give Jenkins more heap space when it´s started as a service under Windows?

I've added to /etc/sysconfig/jenkins (CentOS):

# Options to pass to java when running Jenkins.
#
JENKINS_JAVA_OPTIONS="-Djava.awt.headless=true -Xmx1024m -XX:MaxPermSize=512m"

For ubuntu the same config should be located in /etc/default

How do I properly set the Datetimeindex for a Pandas datetime object in a dataframe?

To simplify Kirubaharan's answer a bit:

df['Datetime'] = pd.to_datetime(df['date'] + ' ' + df['time'])
df = df.set_index('Datetime')

And to get rid of unwanted columns (as OP did but did not specify per se in the question):

df = df.drop(['date','time'], axis=1)

How to write asynchronous functions for Node.js

You seem to be confusing asynchronous IO with asynchronous functions. node.js uses asynchronous non-blocking IO because non blocking IO is better. The best way to understand it is to go watch some videos by ryan dahl.

How do I write asynchronous functions for Node?

Just write normal functions, the only difference is that they are not executed immediately but passed around as callbacks.

How should I implement error event handling correctly

Generally API's give you a callback with an err as the first argument. For example

database.query('something', function(err, result) {
  if (err) handle(err);
  doSomething(result);
});

Is a common pattern.

Another common pattern is on('error'). For example

process.on('uncaughtException', function (err) {
  console.log('Caught exception: ' + err);
});

Edit:

var async_function = function(val, callback){
    process.nextTick(function(){
        callback(val);
    });
};

The above function when called as

async_function(42, function(val) {
  console.log(val)
});
console.log(43);

Will print 42 to the console asynchronously. In particular process.nextTick fires after the current eventloop callstack is empty. That call stack is empty after async_function and console.log(43) have run. So we print 43 followed by 42.

You should probably do some reading on the event loop.

How to delete an app from iTunesConnect / App Store Connect

Here's the answer to my question I got back from Apple support.

Hi XXX,

I am following up with you about the deletion of your app, “XXX”. Recent changes have been made to the App Delete feature. In order to delete your app from iTunes Connect, you must now have one approved version before the delete button becomes available. For more information on the recent changes, please see the "Deleting an App" section of the iTunes Connect Guide (page 96-97):

You can only delete an app from the App Store if it was previously approved (meaning has one approved version).

From iTunes Connect Developer Guide - Transferring and Deleting Apps:

Apps that have not been approved yet can’t be deleted; instead, reject the app.

As of 2016, new changes have been made to iTunes Connect. Here are the screenshots of deleting an approved app from your account.

Check if string contains only letters in javascript

Try this

var Regex='/^[^a-zA-Z]*$/';

 if(Regex.test(word))
 {
 //...
 }

I think it will be working for you.

How do I keep CSS floats in one line?

Add this line to your floated element selector

.floated {
    float: left;
    ...
    box-sizing: border-box;
}

It will prevent padding and borders to be added to width, so element always stay in row, even if you have eg. three elements with width of 33.33333%

jQuery DatePicker with today as maxDate

If you're using bootstrap 3 date time picker, try this:

$('.selector').datetimepicker({ maxDate: $.now() });

Correct file permissions for WordPress

It actually depends on the plugins you plan to use as some plugins change the root document of the wordpress. but generally I recommend something like this for the wordpress directory.

This will assign the "root" (or whatever the user you are using) as the user in every single file/folder, R means recursive, so it just doesn't stop at the "html" folder. if you didn't use R, then it only applicable to the "html" directory.

sudo chown -R root:www-data /var/www/html  

This will set the owner/group of "wp-content" to "www-data" and thus allowing the web server to install the plugins through the admin panel.

chown -R www-data:www-data /var/www/html/wp-content

This will set the permission of every single file in "html" folder (Including files in subdirectories) to 644, so outside people can't execute any file, modify any file, group can't execute any file, modify any file and only the user is allowed to modify/read files, but still even the user can't execute any file. This is important because it prevents any kind of execution in "html" folder, also since the owner of the html folder and all other folders except the wp-content folder are "root" (or your user), the www-data can't modify any file outside of the wp-content folder, so even if there is any vulnerability in the web server, and if someone accessed to the site unauthorizedly, they can't delete the main site except the plugins.

sudo find /var/www/html -type f -exec chmod 644 {} +

This will restrict the permission of accessing to "wp-config.php" to user/group with rw-r----- these permissions.

chmod 640 /var/www/html/wp-config.php

And if a plugin or update complained it can't update, then access to the SSH and use this command, and grant the temporary permission to "www-data" (web server) to update/install through the admin panel, and then revert back to the "root" or your user once it's completed.

chown -R www-data /var/www/html

And in Nginx (same procedure for the apache)to protect the wp-admin folder from unauthorized accessing, and probing. apache2-utils is required for encrypting the password even if you have nginx installed, omit c if you plan to add more users to the same file.

sudo apt-get install apache2-utils
sudo htpasswd -c /etc/nginx/.htpasswd userName

Now visit this location

/etc/nginx/sites-available/

Use this codes to protect "wp-admin" folder with a password, now it will ask the password/username if you tried to access to the "wp-admin". notice, here you use the ".htpasswd" file which contains the encrypted password.

location ^~ /wp-admin {
    auth_basic "Restricted";
    auth_basic_user_file /etc/nginx/.htpasswd;
    index  index.php index.html index.htm;
}

Now restart the nginx.

sudo /etc/init.d/nginx restart